Perhaps you should try some spelling variations:
cohen ryan » john ryan
dang binh » dann bin, dong bin, dang anh
binh tuan » binh thuan, binh tran, dinh tuan
chen ryan » chen siyan, chen yang, chen jian
wong sam » wong sau, wong lai, von sam
tuan vu » thanh vu, tuan hua
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: dang binh tuan vu ((chen ryan) OR (cohen ryan)) john ((wong sam) OR (kong sar)) ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "dang binh tuan vu ((chen ryan) OR (cohen ryan)) john ((wong sam) or (kong sar)) ;~".
• Adding a wildcard symbol may retrieve word variants: dang binh tuan vu ((chen ryan) OR (cohen ryan)) john ((wong sam) or (kong sar)) ;*.