Perhaps you should try some spelling variations:
cheng yang » cheng zhang, chen wang, cheng han
chen yang » chen rong
yan yang » yang yang, yao yang, dan yang
wong sau » wong siu, wong shiu, wong lai
wong sam » wong lai, kong sar, von sam
nan yan » nan ya, wang yan, qian yan
yang yu » yang yue, yang yun, yang yi

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

• Performing a fuzzy search may retrieve terms with similar spellings: nan yan yang yu ((cheng yang) or (chen yang)) john ((wong sau) OR (wong sam)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: nan yan yang yu ((cheng yang) OR (chen yang)) john ((wong sau) OR (wong sam)) ;.
• The words AND, OR and NOT may confuse the search; try adding quotes: "nan yan yang yu ((cheng yang) or (chen yang)) john ((wong sau) OR (wong sam)) ;".
• Adding a wildcard symbol may retrieve word variants: nan yan yang yu ((cheng yang) or (chen yang)) john ((wong sau) OR (wong sam)) ;*.