I know little about this species other than I bought it as an unrooted cutting in the summer of 2018 from Ric Morier on eBay. I suspect that it was something he brought back from one of his trips to Vietnam. It was a fairly pricey cutting at $28 so I suspect that it is somewhat rare. In addition, as of this writing there are no other photos of this plant to be found anywhere.
The cutting rooted quickly and moved from a series of net pots until in flowered in a four inch pot. It is a plant that uses very little water. The leaves are lovely getting a reddish brown color in good light. The flowers have little to no scent, are about 3/8 of an inch in size, and last about 4 days.
Hoya sp. VN Vietnam is a lovely plant with nicely scalloped leaves and gorgeous flowers that is not very hard to grow. It flowers in a reasonable amount of time, and is a plant that I can recommend to everyone. Let’s hope that it becomes more readily available in the future.