Thanks for posting the link. I shall offer my professional 2
cents worth to help improve the bottom line of the sales. 
I have went to this blog few months ago and it had created a big
lasting impression such that I still remember now.
Site-layout
The site layout is grossly under industrial standards, that's
why your friend aren't getting enough traffic to the site and was
not able to retain potential customers.
1. It lack of a bottom navigation bar which
includes the (T&C, Privacy Policy, About us, Contact
details
2. The site is pretty much unsafe for e-commerce due to the fact
that it didn't have SSL in the login page and carts. A good
investment is to beef up the security and add some SSL to the
important pages like
a. login page
b. cart page
c. payment page
3. Lack of a theme. Any website without a theme is sure to meet
it's doom. Personally, I have worked with website designers and
programmers to create awesome blog/website. Their portfolio can be
found at themeforest.net and I purchase the high quality
website design there on a weekly basis. I suggest choosing a
color as a set theme.
4. Your friend's blogshop have enough products to start with
already. One of the main reason why you aren't getting customers
back is because of the photography pictures. The photo reflects
poor photography skills that violate almost all photograph
techniques. 
My suggestion is
to use paid-photographer services. They charge at a reasonable
price, but trust me, the photoquality is definitely much attractive
than that.
5. Does not reflect the scale. Apparantly, this blogshop have an
actual shop at bugis. The feeling of this blog give me the
impression that it's done out of hobby and not business oriented.
There are pretty much more that I can comment, but there are the
few points that you can highlight to your friends.
Read point no.3. Change the whole website, and customers will
come back
In summery, the whole website is a failure. 韩飞官, since I know you, if your
friend hire me to be the website designer and programmer
for $1500 for 90 days, I guarantee sales will come in.
Best regards,
Chin Seng
*copy and past this to your friend* this will get delete
tomorrow by an old lady.
About me:
I am a tutor for 8 years teaching secondary school kids, offer
academic advices to parents, students, company, and recently
I acquired programming knowledge. My ultimate goal is to see
the art of marrying Education and IT together. You can call me an
enthusiast in IT. IT is such a powerful tool that a website can
make or destroy a business. Over the course
of last two year, I learned and gained many
experience in designing and writing programmes for website.
