Perhaps you should try some spelling variations:
thanh dung » thanh duong, thanh tung, thanh hung
cong thanh » dong thanh, cong tan, truong thanh
hieu lang » chieu sang, hieu quang, nhieu tang
toan cao » toan ban
toan tap » toan ban
ho hieu » ho chieu, hoi hieu, nho hieu
va hang » van hang, va nang, va lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho hieu lang - thanh dung va hang ((cong thanh) or (cong trinh)) ((toan cao) or (toan tap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - thanh dung va hang ((cong thanh) OR (cong trinh)) ((toan cao) OR (toan tap)).
• Adding a wildcard symbol may retrieve word variants: ho hieu lang - thanh dung va hang ((cong thanh) or (cong trinh)) ((toan cao) or (toan tap))*.