Perhaps you should try some spelling variations:
yang yang » wang yang, wang yan
yang yan » wang yan, yang fan, yang yao
hua gene » human gene, a gene, hua ren
wong sau » wong siu, wong shiu, wong lai
wong sam » wong lai, kong sar, von sam
yang xi » yang di, yang yi, yang jui
yan ji » yan jiu, ban ji, pan ji

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

• Performing a fuzzy search may retrieve terms with similar spellings: wang ((yang yan) or (yang yang)) hua gene ((yan ji) or (yang xi)) ((wong sau) or (wong sam)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wang ((yang yan) OR (yang yang)) hua gene ((yan ji) OR (yang xi)) ((wong sau) OR (wong sam)) ;.
• Adding a wildcard symbol may retrieve word variants: wang ((yang yan) or (yang yang)) hua gene ((yan ji) or (yang xi)) ((wong sau) or (wong sam)) ;*.