Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
trinh quan » tinh quang, trinh luat, trinh han
hieu manh » chieu xanh, hieu nganh, dieu hanh
hang cong » hang nong, bang cong, thanh cong
dang cong » dung cong
manh toan » thanh toan, anh tuan, tinh toan
hoc hieu » hoc thieu, hoc hien, doc hieu
van than » van thanh, van thang, van tuan

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