Perhaps you should try some spelling variations:
cong thanh » cong trinh, truong thanh
dong thanh » truong thanh
hieu xanh » chieu xanh, hieu manh, hieu nganh
tranh cua » doanh cua, manh cua
cua trung » cua truong, xuan trung, cua nhung
doc hieu » toc thieu, hoc thieu, hoc hien
cong tan » cong tac, cong san, cong ty
toan tap » toan ban

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