A couple months ago I started to use Chopp.vn to order some groceries that I needed that was hard to find at the local markets such as Family Mart or Vinmart. So far I have used them several times now. The service is good and a couple times they did call when an item was missing.
With the extra fees, I found it was an equivalent of taking a taxi to Lotte Mart. Actually possibly a bit cheaper too and you did not have to wait in line. The delivery is always within the allotted time when you book an order in the app.
To use Chopp.vn, it is best to use the app instead of the website. Links are below:
Apple App Store: https://itunes.apple.com/us/app/chopp/id1063190708