Perhaps you should try some spelling variations:
thanh tung » thanh cong
hieu lang » chieu sang, hieu quang, nhieu tang
cong danh » cuong danh, cong dan, cong thanh
danh toan » manh toan, anh toan, dan toan
doc hieu » toc thieu, hoc thieu, hoc hien
van hang » van khang, van hoang, van thang
toan tap » toan ban
va nang » van nang, da nang, kha nang

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: doc hieu lang - thanh tung ((van hang) OR (((va nang) OR (cam nang)))) cong danh toan tap~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu lang - thanh tung ((van hang) or (((va nang) OR (cam nang)))) cong danh toan tap~".
• Adding a wildcard symbol may retrieve word variants: doc hieu lang - thanh tung ((van hang) or (((va nang) OR (cam nang)))) cong danh toan tap*.