People,
These bigfoot-type creatures mentioned below seem similar to the Almas of Central Asia, whose page I will put at the bottom. What you want to take with you as you read the two pages below is that the Almas were encountered in underground caves. Just because the creatures below were encountered in the Vietnamese jungle doesn't mean that they live on the surface.
Almas: http://www.holloworbs.com/Almas_of_Asia.htm
Cheers!