Perhaps you should try some spelling variations:
yang yang » wang yang, wang yan
chen yang » chen rong
john kong » john king, john wong, john bonn
john song » john wong, john bonn, john ngosong
yang yu » yang yue, yang yun, yang yi
yu chen » yu cheng, yi chen, yulu chen
wang » wing, wan

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

• Performing a fuzzy search may retrieve terms with similar spellings: (wang or lang) yang yang yu chen yang ((john kong) or (john song)) sar ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (wang OR lang) yang yang yu chen yang ((john kong) OR (john song)) sar ;.
• Adding a wildcard symbol may retrieve word variants: (wang or lang) yang yang yu chen yang ((john kong) or (john song)) sar ;*.