Perhaps you should try some spelling variations:
chen yang » chen rong
john song » john bonn, john ngosong
john wong » john bonn
wang anh » dang anh, wang yang, wang yan
anh tran » oanh tran, anh tuan, binh tran
tran hua » tan hua, tuan hua, tran duc
hua chen » jui chen, yu chen, a chen

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

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