I think that this is not just the loveliest Vietnamese cover I have received, but one of the loveliest covers in general as well.
The initial purpose of the trade was a postcard or more precisely a maxi-card, which i honestly never expected to arrive packed in something like this.
The stamps are from 2008/2009.
The 2008 stamps are the one in the top-right-corner, which is from a joint issue with Singapore, presenting Flora, and here the (in)famous Durian is shown. Regardless of all the stories I had heard about the Durian, I would LOVE to try it.
And the other 2008 stamp is the Olympic one, or the only one which is not put the way it should be. It represents the Olympic Games in Beijing 2008, and this stamp in particular presents the Wushu, which is a full-contact sport derived from traditional Chinese Martial Arts.
Regarding the 2009 stamps, the most present is the Fish one (set of 4 stamps), whose scientific name is Botia Macracanthus, or if you find that hard to remember, you can use its widely accepted name of Clown Loach.
Another 2009 stamp is the Year of the Tiger one (from what ive seen, EXTREMELY popular philatelic topic). It comes in a set of 2 stamps.
And the last one is the stamp with the flower, again coming from a set of 4 stamps.