Perhaps you should try some spelling variations:
hieu nganh » vien nganh, hiem ngan, hieu manh
hanh tranh » canh tranh, hanh trinh, hanh trang
nhung cong » dung cong, thong cong, hang cong
tranh cua » doanh cua, manh cua
dang cong » dung cong
doc hieu » toc thieu, hoc thieu, hoc hien
van toan » van tan, van thanh, manh toan
van tuan » van quan, van ban, anh tuan

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu nganh - hanh tranh cua ((nhung cong) or (dang cong)) ((van toan) or (van tuan)) ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu nganh - hanh tranh cua ((nhung cong) OR (dang cong)) ((van toan) OR (van tuan)) ban.
• Adding a wildcard symbol may retrieve word variants: doc hieu nganh - hanh tranh cua ((nhung cong) or (dang cong)) ((van toan) or (van tuan)) ban*.