Perhaps you should try some spelling variations:
hieu manh » chieu xanh, hieu nganh, dieu hanh
tranh cua » doanh cua, manh cua
cong cong » cong dong, trong cong, dang cong
dung cong » dung trong
hoc hieu » hoc thieu, hoc hien, doc hieu
san phan » san pham, van phan, dan phan
sat phan » sat nhan, vat phan, xuat phan

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 - canh tranh cua ((cong cong) or (dung cong)) ((san phan) or (sat phan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu manh - canh tranh cua ((cong cong) OR (dung cong)) ((san phan) OR (sat phan)) cau.
• Adding a wildcard symbol may retrieve word variants: hoc hieu manh - canh tranh cua ((cong cong) or (dung cong)) ((san phan) or (sat phan)) cau*.