Perhaps you should try some spelling variations:
wang wang » wang yang, wang liang, wang yong
yang john » young john, king john, yang jin
john wong » john song, john bonn
tuan hua » tuan vu, yuan hui
dan yang » daun yang, tan yang, wang yang
wong sam » wong sau, wong lai, kong sar
tan hua » wang hua, tan chia, tan puay

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

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