Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, hieu manh
hanh trang » thanh trung, canh tranh, minh trang
hanh trinh » canh tranh, hanh chinh
dung cong » dung trong
khoan cam » khoa cam, khoan va, phan cam
hoc hieu » hoc thieu, hoc hien, doc hieu
cong san » cong tac
khan cap » khan ap, than cap, phan cac
va dung » van dung, va duong, vat dung

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 - ((hanh trang) OR (hanh trinh)) va dung cong san ((khan cap) OR (khoan cam))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu nganh - ((hanh trang) or (hanh trinh)) va dung cong san ((khan cap) OR (khoan cam))~".
• Adding a wildcard symbol may retrieve word variants: hoc hieu nganh - ((hanh trang) or (hanh trinh)) va dung cong san ((khan cap) OR (khoan cam))*.