Perhaps you should try some spelling variations:
hieu manh » chieu xanh, hieu nganh, dieu hanh
nang sang » nang song, nong san
trong san » trong cac, cong san, dong san
hoc hieu » hoc thieu, hoc hien, doc hieu
qua dung » quang dung, qua song, qua cong
san than » sang than, san thanh, ban than
than cap » khan cap, thanh lap, thanh cac

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 - nang sang ((qua dung) or (su dung)) trong san than cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - nang sang ((qua dung) OR (su dung)) trong san than cap.
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - nang sang ((qua dung) or (su dung)) trong san than cap*.