Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, hieu manh
canh trinh » canh tranh, hanh trinh, canh tinh
trinh xay » trinh ky
hoc hieu » hoc thieu, hoc hien, doc hieu
cong dan » cong tan, huong dan, cong dong
cong san » cong tac
phan dau » phan tu, hang dau

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 - canh trinh xay dung ((cong dan) or (cong san)) phan dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu nganh - canh trinh xay dung ((cong dan) OR (cong san)) phan dau.
• Adding a wildcard symbol may retrieve word variants: hoc hieu nganh - canh trinh xay dung ((cong dan) or (cong san)) phan dau*.