Perhaps you should try some spelling variations:
tuan china » wuhan china, can china, taiwan china
china gene » china gender, china agenda
yan tuan » yan guan, yan yuan, anh tuan
yang jui » yang judy, yang xi, yang yi
wong sam » wong sau, wong lai, kong sar
wong siu » wong shiu, kong siu, wong sau
wan yan » wang yan, nan yan, wai yan

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: wan yan tuan china gene ((yang jui) OR (yang di)) ((wong sam) OR (wong siu)) ;~.
• Adding a wildcard symbol may retrieve word variants: wan yan tuan china gene ((yang jui) or (yang di)) ((wong sam) or (wong siu)) ;*.