Perhaps you should try some spelling variations:
hieu lang » chieu sang, hieu quang, nhieu tang
anh tang » anh bang, anh dang, anh nang
cong van » cong vang, song van, cong tan
cong san » cong tac
thai cao » tai cao, thoai cac, thuat cao
tang va » trang va, tang van, thang va
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: hoc ((chinh sach) or (hieu lang)) - anh tang va hang ((cong van) or (cong san)) thai cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chinh sach) OR (hieu lang)) - anh tang va hang ((cong van) OR (cong san)) thai cao.
• Adding a wildcard symbol may retrieve word variants: hoc ((chinh sach) or (hieu lang)) - anh tang va hang ((cong van) or (cong san)) thai cao*.