Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, nghiep nganh
nhung cong » dung cong, thong cong, nhung don
hieu manh » chieu xanh, dieu hanh, hien hanh
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
hang cong » dang cong, hang nong, bang cong
tinh cua » trinh cua, sinh cua, tinh chat
san toan » van toan, dan toan, manh toan
toan cao » toan ban, toan tap

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