Bumping this down.

Mang Cau is Anona squamosa, usually called sweetsop or sugar apple here. Considered native in most of Southeast Asia but had its origins in South America.

I don't know about hoa mai but the other common Mickey Mouse plant here is very easy to grow from seeds. I've never tried to grow them but the birds seem to enjoy the fruits and spread the seeds all over the yard. There's several growing right now.

Thanks, Eggo for your help  I did not think I would get a response. It looks like Hoa mai might well be the Mickey Mouse Plant (Ochna serrulata). Since they are from Vietnam, it will be interesting to compare them to the web pictures. I am glad to know the good luck plant is an easy germinator. The annona I know how to germinate  the other I was concerned about.

Does anyone know where i can get ube plants to grow for myself. I purchased a purple potato plants and it's not the same. Can someone tell me where i can purchase the ube plant.

eggo,
The proper spelling is Annona squamosa.

purpleladypurplelady,
Look here for sources: sources

eggo,
The proper spelling is Annona squamosa.

purpleladypurplelady,
Look here for sources: sources, also be sure to check the FAQ of this forum for additional sources.