Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, nghiep nganh
canh nhung » anh nhung, hanh nhung, doanh nhung
nhung cong » dung cong, thong cong, hang cong
hieu manh » chieu xanh, dieu hanh, hien hanh
hanh tran » hanh trang, thanh tran, hanh tram
tran canh » tran manh, tran anh, tran danh
san toan » van toan, manh toan, xuan toan
dan toan » van toan, dan than, manh toan

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) OR (hieu nganh)) - hanh tran canh nhung cong ((san toan) or (dan toan)) cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu manh) OR (hieu nganh)) - hanh tran canh nhung cong ((san toan) OR (dan toan)) cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu manh) OR (hieu nganh)) - hanh tran canh nhung cong ((san toan) or (dan toan)) cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu manh) OR (hieu nganh)) - hanh tran canh nhung cong ((san toan) or (dan toan)) cao*.