Perhaps you should try some spelling variations:
theo hieu » theo chieu, theo tieu, thien hieu
hieu lang » chieu sang, hieu quang, nhieu tang
anh dang » anh dong, anh dung, anh bang
cua hang » cua dang, cua nhung, cua ban
cong tac » cong ty
tac toan » tap toan, tam toan, hach toan
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: theo hieu lang - anh dang ((cua hang) or (cua cong)) cong tac toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo hieu lang - anh dang ((cua hang) OR (cua cong)) cong tac toan cau.
• Adding a wildcard symbol may retrieve word variants: theo hieu lang - anh dang ((cua hang) or (cua cong)) cong tac toan cau*.