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
song min » song ming, gong min, jong min
yang xi » yang yi, yang jui
von sam » von sap, von scham, von sach
von sa » von sap, von sl, von sach
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 than china gene ((yang xi) OR (yang di)) ((((von sa) OR (von sam))) OR (song min)) ;~.
• Adding a wildcard symbol may retrieve word variants: wang yan than china gene ((yang xi) or (yang di)) ((((von sa) or (von sam))) or (song min)) ;*.