Perhaps you should try some spelling variations:
china gene » china gender, china agenda
yan zhang » yuan chang, bin zhang, han chang
yang jui » yang judy, yang xi, yang yi
wong sam » wong lai, kong sar, von sam
wong sau » wong siu, wong shiu, wong lai
yan han » man han, kang han, yan clan
wang » wing, wan, lang

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: wang ((yan han) OR (yan zhang)) china gene ((yang jui) OR (yang di)) ((wong sam) OR (wong sau)) ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang ((yan han) OR (yan zhang)) china gene ((yang jui) or (yang di)) ((wong sam) or (wong sau)) ;~".
• Adding a wildcard symbol may retrieve word variants: wang ((yan han) OR (yan zhang)) china gene ((yang jui) or (yang di)) ((wong sam) or (wong sau)) ;*.