It depends on a lot of different things. Some Asian girls only want to marry Asian guys so they can be traditional and shit, or their parents say so. The majority of Asian girls I see are with Asian guys. But yeah a larger than normal proportion of Asian girls will go for white guys, I guess because we are more masculine looking, maybe bigger dicks too I dunno. If you go to an Asian country you'll have Asian women all over you, but that's mostly because they assume you're rich so whatever.
I also found some interesting historical info on Wikipedia: https://en.wikipedia.org/wiki/Eurasian_(mixed_ancestry)#Vietnam
But they might've only done that for political gain, not because they got off to it or anything.