This thread provides some information about Asia/Asians that you have or have not heard before.
"The following is a list of ethnic slurs, also known as ethnophaulisms, that are, or have been, used to refer to members of a given ethnicity (or, in some cases, nationality, region, or religion) in a derogatory or pejorative manner. The term is listed, followed by its primary user(s) and a definition.
Terms on this list vary greatly in offensiveness. Many are taboo. Some are used more widely than might be imagined based on their "definition"; for example, Boatie can be used to refer to any Vietnamese person, a form of metonymy. The key here is that the person using the slur cares so little about the target, that the person's actual background is irrelevant. The motivation for using an ethnic slur is often racism or bigotry.
It is not uncommon for minority groups to adopt an originally disparaging term and use it of themselves, as an act of self-assertion. However, they may be extremely offended if it is used by others. Nigger is an extreme example."
(Copied from http://www.nationmaster.com/encyclopedia/List-of-ethnic-slurs)