Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, truong thanh
hieu xanh » chieu xanh, hieu manh, hieu nganh
tranh cua » doanh cua, manh cua
cua nhung » va nhung
doc hieu » toc thieu, hoc thieu, hoc hien
cong tan » cong tac, cong san, cong ty
phan dau » phan tu, hang dau
hang tai » hang va, dung tai

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 xanh - canh tranh cua nhung ((cong tan) OR (cong thanh)) ((phan dau) or (hang tai))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu xanh - canh tranh cua nhung ((cong tan) OR (cong thanh)) ((phan dau) OR (hang tai)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu xanh - canh tranh cua nhung ((cong tan) OR (cong thanh)) ((phan dau) or (hang tai))".
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - canh tranh cua nhung ((cong tan) OR (cong thanh)) ((phan dau) or (hang tai))*.