Perhaps you should try some spelling variations:
hieu manh » chieu xanh, hieu nganh, dieu hanh
hanh dung » thanh dung, anh dung, hanh dong
dung cong » dung trong
hoc hieu » hoc thieu, hoc hien, doc hieu
anh tang » anh bang, anh dang, anh nang
cua dung » cua dang, cua dong, qua dung
cong tan » cong tac, cong san, cong thanh
tan than » tan thanh, tan tran, ban than
than cau » toan cau, phan cau, than cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hieu manh - ((hanh dung) or (anh tang)) cua dung cong tan than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - ((hanh dung) OR (anh tang)) cua dung cong tan than cau.
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - ((hanh dung) or (anh tang)) cua dung cong tan than cau*.