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

You may be able to get more results by adjusting your search query.

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