Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, hieu manh
nhung cong » dung cong, thong cong, hang cong
hoc hieu » hoc thieu, hoc hien, doc hieu
tram van » tran van, trang van, tranh van
cong tac » cong ty
tac than » tac thanh, tam than, tac nhan
than cao » toan cao, thai cao, than cap
tam van » nam van, dam van, tom van

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: hoc hieu nganh - hanh ((tram van) OR (tam van)) nhung cong tac than cao~.
• Adding a wildcard symbol may retrieve word variants: hoc hieu nganh - hanh ((tram van) or (tam van)) nhung cong tac than cao*.