Perhaps you should try some spelling variations:
doanh doanh » toan doanh, doanh hoan, doanh thanh
hieu manh » chieu xanh, hieu nganh, dieu hanh
luan hang » luan nang, luan han, luan tang
luan hung » luan chung, lan hung, luan ung
hoc hieu » hoc thieu, hoc hien, doc hieu
van toan » van tuan, van tan, van thanh
dan than » dan chan, ban than, van than

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 - doanh doanh ((luan hang) OR (luan hung)) cong ((van toan) or (dan than)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - doanh doanh ((luan hang) OR (luan hung)) cong ((van toan) OR (dan than)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu manh - doanh doanh ((luan hang) OR (luan hung)) cong ((van toan) or (dan than)) cau".
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - doanh doanh ((luan hang) OR (luan hung)) cong ((van toan) or (dan than)) cau*.