Perhaps you should try some spelling variations:
john ngosong » john song
wang yang » wang yan, wang liang, wang yanling
yang tran » nang trang, yang dean, yang fan
chen yang » chen rong
tran duc » tran dat, tran dai
ren yang » ren yan, dan yang, pei yang
sam » same, sham, syam

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 tran duc ((ren yang) or (chen yang)) john ngosong sam ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wang yang tran duc ((ren yang) OR (chen yang)) john ngosong sam ;.
• Adding a wildcard symbol may retrieve word variants: wang yang tran duc ((ren yang) or (chen yang)) john ngosong sam ;*.