It's a common misconception from especially caucasian men that other ethnicities look "all alike".
There is science involved but that's too long to go into right now.
Sufficent to say, the poster above me is correct, the more time you spend with people outside of your specific ethnic group you learn to differentiate. This same principle applies regardless if we're talking asians or people of african descent and so forth.
Having dated guys of (among others) chinese, philippino and thai descent and have friends from other places I can tell you, they are not as similar as you might think. At least not in the way you are implying.
If the articles I read on the subject are correct though, asians who spent very little time with, say, white men, would look at us in a similar way though.
