Perhaps you should try some spelling variations:
nhung cong » thong cong, hang cong, nhung don
hanh trinh » canh tranh, hanh chinh
hieu xanh » chieu xanh, hieu manh, hieu nganh
trinh cua » tinh cua, trinh luat, trinh quan
dung cong » dung trong
doc hieu » toc thieu, hoc thieu, hoc hien
dan toan » van toan, dan than, manh toan
van than » van thanh, van thang, van 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 xanh - hanh trinh cua ((nhung cong) OR (dung cong)) ((dan toan) or (van than)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu xanh - hanh trinh cua ((nhung cong) OR (dung cong)) ((dan toan) OR (van than)) cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu xanh - hanh trinh cua ((nhung cong) OR (dung cong)) ((dan toan) or (van than)) cau*".