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 van » cong vang, cong san, song van
van phan » van phong, van thanh, luan 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 van phan dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - cach mang ((cua dung) OR (cua dang)) cong van phan dau.
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - cach mang ((cua dung) or (cua dang)) cong van phan dau*.