The Bible says that mankind originated from Noah's three sons. That is an interesting argument, but Mongolians in East Asia are genetically distant from the descendants of Shem. In Genesis, not only the descendants of Noah, but also the Nephilim, a mixed race of angels and humans. Some argue that the Nephilim are a mixed race of aliens and humans.
Only God will know the truth!
Vietnamese don't really have to be against the Chinese people but I think some are or maybe many are. But the real problem has been the Chinese government itself. The most popular last name in Vietnam is Nguyen.
Nguyen is probably the last name of the king of Vietnam, who made Vietnam independent by fighting China.