Perhaps you should try some spelling variations:
than china » tuan china, han china, wuhan china
china gene » china gender, china agenda
yan than » van thanh, yan zhang, yan clan
yang jui » yang judy, yang xi, yang yi
wong siu » wong shiu, kong siu, wong sau
von sap » von sa, von sam, von sach
wang » wing, wan

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 OR lang) yan than china gene ((yang jui) OR (yang di)) ((von sap) OR (wong siu)) ;~.
• Adding a wildcard symbol may retrieve word variants: (wang or lang) yan than china gene ((yang jui) or (yang di)) ((von sap) or (wong siu)) ;*.