Perhaps you should try some spelling variations:
nhung cong » thong cong, hang cong, nhung don
hieu xanh » chieu xanh, hieu manh, hieu nganh
tranh cua » doanh cua, manh cua
dung cong » dung trong
doc hieu » toc thieu, hoc thieu, hoc hien
phan cau » phan cac, phan tu, phan lap
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: doc hieu xanh - canh tranh cua ((nhung cong) OR (dung cong)) dan ((phan cau) or (phan dau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu xanh - canh tranh cua ((nhung cong) OR (dung cong)) dan ((phan cau) OR (phan dau)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu xanh - canh tranh cua ((nhung cong) OR (dung cong)) dan ((phan cau) or (phan dau))".
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - canh tranh cua ((nhung cong) OR (dung cong)) dan ((phan cau) or (phan dau))*.