Interviewee
BUS 450
Consumers judge & select a brand of dietary supplements
Buy for
Purpose
Criteria used
Brand’s
selection
Asking
recommendation
from relatives,
friends who have
knowledge
(WOM)
Based on social
reviews,
relationships
(friends rather
than reviews on
websites)
Don’t believe on
sellers
Vu Thi Ly
(23 yrs old)
(don’t
consider)
Self
(vitamin E, A,
C)
Collagen,
bones
Improve
resistance, less
direct effects
compared to
medicine
1/ Truth worthiness
of the brand
2/ Good quality
3/ Ingredients table
4/ Reviews
Nguyen Minh
Huy
(21 yrs old)
(don’t
consider)
Self (vitamin
D, Omega 3,
White protein)
Good for brain,
bones, nerve
1/ Ingredients gr
2/ Truth worthiness
3/ Brand reputation
Le Thi Van
Anh (25 yrs
old)
(don’t
consider)
Thai Thi
Phuong Nha
(27 yrs old)
(don’t
consider)
Luong Nguyen
Ngoc Tram (21
yrs old)
(don’t
consider)
Self and mom
Good for brain
and eyes
1/ Good quality
2/ High truth
worthiness
3/ Price
Based on reviews
 compare
quality / brands
 final decisions
Self and mom
(collagen)
Skin (antiaging), eyes
(brighter)
1/ Good quality
2/ Price
3/ Reviews
Based on reviews
from friends,
relatives,
colleagues.
Self and mom
(Omega 369,
Blackmores,
Healthy jelly)
1/ Good quality
2/ Truth worthiness
(Brand origin)
3/ Reviews
(2 products the same
supplements but
different prices 
compare prices 
ingredients  if
ingredients = 
choose lower price)
Based on reviews
on websites
Tran Vinh
Phuoc (54 yrs
old)
Self
Improve
brighter eyes,
support
cardiovascular,
immune system,
strengthen
digestive
system, smooth
hair, hair grow,
reduce hair loss,
smooth skin,
blurred, antiaging
Glucosamine
supplements,
slow joint
degeneration,
1/ Quality
2/ Price
A good quality brand
recognition based on
Based on
1/ online
information
(Healthy beauty,
(consider
recommend
products)
joint
lubrication,
cartilage
regeneration
Fe supplements
 hypotension
product origin,
factory standard
Aladin, Thuoc
Yeu Thuong),
2/ colleagues
1/ Price
2/ Quality
Based on friends’
recommendations
Self
Whey protein,
muscle
supplements
1/ Quality
2/ Price
Based on
influencers
(experienced
users)
Trang Sao
Nghi (24 yrs
old)
(don’t
consider)
Tran Vu
Phuong Lam
(23 yrs old)
(don’t
consider)
Vo Thi My
Linh (56 yrs
old)
(don’t
consider)
Self
Self then
recommend for
others
Protein, eyes,
body
purification,
heart
Quality
1/Truth worthiness
of the brand
2/ Price
3/ Used experience
Based on
1/ selfexperience,
knowledge
2/ information
found
3/ friends &
colleagues’
recommendations
(afraid of
EWOM)
Dang Nguyen
Phuong Thy
(21 yrs old)
(don’t
consider,
believe on
youtube’s
reviews)
Thai Minh
Duy (26 yrs
old)
(consider,
believe in
sellers but
lesser than
friends…)
Nguyen Phuoc
Quy Yen (25
yrs old)
Self
Vitamin,
vegetable,
water, smooth
skin
supplements
1/ Quality
2/ Truth worthiness
3/ Reputation
New brand judge:
clear product origin
Self & family
Gain weight
supplements
(Yakuho)
1/ Quality
2/ Price
3/ Truth worthiness
New brand judge:
1/ product origin
 truth worthiness
2/ Price
1/ experienced
users
2/ reviews on
Youtube + search
information on
websites
3/ WOM from
relatives
1/ self-experience
2/ information
found
3/ friends &
relatives’
recommendations
Self & gifts
Vitamin C, E,
D, Fat Burn,
Protein,
Collagen,
1/ Reviews products 1/ Reviews
(Youtube,
2/ Experienced
Webpages)
users
Vegetable,
Fiber
supplements
2/ Ask from
surrounding people
New brand judge:
1/ Reviews
2/ Chance to change
(khi lờn thuốc thì
đổi)
Nguyen Vinh
Minh Thanh
(56 yrs old)
Self and gifts
Blood
circulation to
the brain, lose
weight, brighter
eyes
1/ self-needs
2/ truth-worthiness
brand (based on
prestige, medical
license)
Luong Trung
Nghia (60 yrs
old)
Self
1/ experience users
2/ online reviews
Bui Quang
Hung (28 yrs
old)
(consider)
Self & relatives
Ginkgo 3
(brain),
Glucosamine
(bone)
supplements
Vegetable,
brighter eyes,
bones
supplements
Hoang Co
Thach (33 yrs
old)
(don’t
consider)
Self
Nguyen Cam
Phuong Linh
(20 yrs old)
(not consider
on sellers, but
Self and others
Brain, memory
improvement,
turmeric nano
for intestinal
tract (đường
ruột), digestion,
stomach
supplements
Brain, memory
supplements
1/ quality (covers
for
truthworthiness)
2/ price
New brand’s
selection
1/ brand origin
2/ brand reputation
1/ quality
2/ price
Truth worthiness of
new brand selection
1/ credibility / truth
worthiness brand
image
2/ quality
3/ price
1/ selfexperience and
information
(platform from
experienced
users, friends…)
2/ reviews
(WOM)
3/ Caution on
internet
4/ Proposal of
sellers
1/ refer to many
sources
(friends, reviews)
2/ doctors’
recommendations
1/ reviews
2/ relatives &
friends
on bad
reviews)
based on product’s
popularity
Công dụng trung
hoà
1/ reviews of
relatives
2/ reviews /
comments of online
users
New Product:
1/ consider
supplements
(quality) first
2/ then price
3/ product origin or
brand of product
4/ feedback
1/ quality (suitable
ingredients)
2/ truth worthiness
brand
3/ reasonable price
New brand’s
criteria:
1/ suitable
ingredients
2/ truth worthiness
brand
3/ price comparison
1/ experienced
users
Compare
feedbacks 
price  buy
1/ reviews
(Facebook)
But experienced
users are more
trustful
1/ web (users)
(livestream,
facebook such as
likes, shares)
Phan Thi
Tuyet Ngan
(23 yrs old)
(consider
sellers)
Self
[order]
Skin
supplements
Nguyen Thi
Hoa Phuong
(27 yrs old)
(don’t
consider)
Self + mom
[online > store]
Skin
supplements
(aqua-rich, hair
& nail
supplements)
Tran Thanh
Lam (22 yrs
old)
(don’t
consider)
Tran Huynh
Thao Nhi (17
yrs old)
Self
[store > online]
Eyes, protein
supplements
Self
[store > online]
Lose weight,
eyes
supplements
1/ quality
Nguyen Thi
Hien (30 yrs
old)
Self
[online > store]
Smooth skin
supplements,
body
supplements
1/ price (high)
High price  high
quality
2/ quality
3/ truth worthiness
and
Brand reputation
1/ recommends of
relatives
2/ reviews of
experienced users
on internet
Le Van Thien
(32 years old)
(consider)
Parents
Canxi, sleep
supplements
Vuong Thanh
Hien (22 yrs
old)
(consider if
information is
not enough)
Self
[store]
 maintain the
same product
 don’t use if
different
comments
Control weight
supplements
Le Huynh Thi
Diem Ha (42
yrs old)
(not consider)
Self
[store]
 try if
products are
different
Protein
supplements
Le Tan Loi (24
yrs old)
(consider
sellers)
Mom
[store > online]
Brain, bone,
eyes
supplements
Truong Thi
Anh Tuyet (49
yrs old)
(not consider)
Self
[store > online]
 don’t try
new product
Brain, eyes,
fiber
supplements
New brand’s
criteria:
Product origin 
judge quality
1/ quality
2/ truth worthiness
New brand’s
criteria:
Reputation of
brand  good
quality (based on
influencers)
1/ truth worthiness
brand
2/ brand reputation
1/ reviews from
platform, friends
2/ ingredients to
satisfy needs
Important 
ingredients and
brand reputation [I]
(based on price)
New product’s
selection:
Product origin
1/ quality
2/ price (high)
1/ product origin
2/ reviews from
experienced users
1/ watch reviews
on website,
comments
1/ self-search
2/ online reviews
(google)
Read information
online  come to
store to hear
recommendations
of sellers
3/ friends’
reviews
1/ friends >
online users
1/ TV
information
 search on
website
 go to store to
receive
recommendations
 buy or not buy
1/ believe in
relatives > sellers
or online users
2/
recommendations
& search
information
1/ online reviews
 influencers
2/
recommendations
from friends
Tran Thanh
Ngan (21 yrs
old)
(not consider
sellers)
Self & mom
[online > store]
 try new
products
Vitamin A, E,
D, protein
supplements
Tran Thi Thu
Hoai (21 yrs
old)
(not consider
to switch
brand)
Self & others
[online > store]
 not try new
product
Health, protein
supplements
Huynh Yen
Linh (23 yrs
old)
(not consider)
Self & family
[online order >
store]
 not try
Skin, eyes, an
ngon
1/ truth worthiness of
brand
2/ reviews of
experienced users
New brand’s
selection:
Quality based on
product origin
Truth worthiness
supported by
popularity and
online-reviews
1/ self-search
2/ friends and
family’
recommendations
Trinh Hai
Dang (31 yrs
old)
(not consider)
Self
[online]
Health
supplements
1/ the number of
users
2/ price
3/ recommendations
New brand’s truth
worthiness:
Product origin
Nguyen Thi
Ngoc Anh (27
yrs old)
Self and family
[store]
Protein, bone
supplements
1/ truth worthiness
of brand
1/ from friends,
relatives,
influencers
Search
information 
compare price to
seek for quality
 ask friends /
relatives  buy
1/ main website
of product
1/ Truth worthiness
of brand
2/ Quality
3/ Result
4/ Reviews
5/ Price (suitable)
New brand’s
selection:
Quality
(supplements)
1/ Popularity of
products and truth
worthiness
(based on inspection
paper, reliable
website via online
users)
2/ suitable to body
1/ self-search
2/ sellers’
recommendation
(not consider)
2/ reviews from
friends / relatives
3/ self-search
Tran Duy
Ngoc (28 yrs
old)
(believe users
than
manufacturers)
(consider
sellers)
Self & gifts
[store and
online]
 try new
product
Vitamin, antiaging of bones
and skin
supplements,
collagen
Dang Huynh
Ngoc Nu (21
yrs old)
Self
[online]
 not try new
product
Omega 3,
everything
Dang Quoc
Viet (21 yrs
old)
Self & gifts
[store]
 not try new
product
self
[store]
Brain, sleep
supplements
Nguyen Anh
Tuyet (30 yrs)
Nguyen Thi
Hoang Oanh
Nguyen Hoang
Nam
Mai Duy
Khuong x
Self
[online]
Nguyen Thi
Hanh x
Self, mom,
aunt
[online]
1/ truth worthiness
of brand /
manufacturer
2/ reviews of online
users, relatives 
support for truth
worthiness
3/ ingredients table
4/ sellers’ suggestion
5/ influencers
6/ price (if 2
products have the
same supplements,
and influencers)
1/ quality
2/ truth worthiness of
the product
3/ influencers
1/ quality
2/ friends’
recommends
1/ Quality (brand
reputation)
2/ Price
1/ brand reputation
2/ feedbacks
1/ WOM relatives
2/ Reviews
3/ influencers
4/ sales
1/ supplements
2/ quality
3/ time
4/ product origin
1/ quality
2/ popularity
3/ price
4/ ingredients
2/ group of
reviews
3/ google
information
4/ friends’
recommends
1/ relatives,
friends > sellers
2/ reviews  the
reputation,
product origin
1/ Read reviews
 evaluate
2/ Ask relatives,
friends > online
users
1/ friends’
reviews
1/ friends
2/ PT
1/ self-search
2/ feedbacks
3/ experienced
users
Pham Vu
Quynh Nhi
(not)
self
[online]
Vo Ngoc Minh
Anh
Self & parents
[online]
Nguyen Thi
Thanh
Self
[store]
Heart
1/ truth worthiness
2/ ingredients
3/ results
4/ knowledge
1/ quality
2/ truth worthiness
3/ price
4 product origin
Truth worthiness
(brand name)
Web
Experienced users
Internet / relatives
Friends
Functional food: ví dụ như nước uống trà diệp lục
Diatery supplement: không kiểm nghiệm lâm sàng, không ai chứng nhận, tiêu chuẩn hay tiêu
chí thấp hơn so với nghiêm ngặt của thuốc.
Sự khác nhau giữa thực phẩm chức năng và thuốc
Thuốc: qua nhiều thứ, qua kiểm tra lâm sàng của công ty, được sự xác nhận đánh giá của FDA
và bộ y tế.
Thực phẩm chức năng: không chứng minh lâm sàng, không có nghiên cứu về tác dụng phụ
(sicence effects). Khi uống vô, không có tác dụng lắm, hấp thu hạn chế.
Note: làm rõ sự khác biệt
Thành phần bổ sung và thực phẩm chức năng là gì?
Heuristic hay functional food
Dựa vào qui tắc nào mà đánh giá sp?
Đọc
1. Abstract & introduction
2. Literature review [doc ky] (background and theorical framework), hypothesis
[Method: doc lay du lieu, ko can doc phan tich du lieu]
3. Results  gia thuyet nao xac nhan, gia thuyet nao bac bo