Perhaps you should try some spelling variations:
hieu manh » chieu xanh, hieu nganh, dieu hanh
hoc hieu » hoc thieu, hoc hien, doc hieu
cua dung » cua dong, qua dung, cua rung
cua dang » cua cong, cua ban
cong tan » cong tac, cong san, cong thanh
tan phan » toan phan, than phan, van phan
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 manh - cach mang ((cua dung) OR (cua dang)) cong tan phan dau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu manh - cach mang ((cua dung) OR (cua dang)) cong tan phan dau".
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - cach mang ((cua dung) OR (cua dang)) cong tan phan dau*.