Perhaps you should try some spelling variations:
ethan john » tian john
tuman john » dugan john, tian john, turn john
wang anh » dang anh, wang yang, wang yan
anh tuan » anh tran, dinh tuan, oanh tran
tuan hua » tan hua, tuan vu, yuan hui
wong sam » wong sau, wong lai, von sam
hua ren » hua chen
sar » sara, star, saur

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

• If you are trying to use Boolean operators, they must be ALL CAPS: wang anh tuan hua ren ((tuman john) OR (ethan john)) ((wong sam) OR (kong sar)) ;~.
• Adding a wildcard symbol may retrieve word variants: wang anh tuan hua ren ((tuman john) or (ethan john)) ((wong sam) or (kong sar)) ;*.