Perhaps you should try some spelling variations:
dang cong » dung cong
hieu lang » chieu sang, hieu quang, nhieu tang
anh nang » ganh nang, anh bang, anh sang
anh dang » anh dong, anh dung, anh bang
cua dang » cua cong, cua ban
cong tac » cong ty
tac toan » tap toan, tam toan, hach toan
toan cau » toan cao, toan ban, toan tap
ho hieu » ho chieu, hoi hieu, nho hieu

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 - ((anh nang) or (anh dang)) cua dang cong tac toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho hieu lang - ((anh nang) OR (anh dang)) cua dang cong tac toan cau*.