Perhaps you should try some spelling variations:
hieu xanh » chieu xanh, hieu manh, hieu nganh
lanh manh » lanh tranh, lan anh, van manh
cua thong » cua thuong, cua khong, suat thong
doc hieu » toc thieu, hoc thieu, hoc hien
cua tong » cua cong, cua dong, cua nong
cong dan » cong san, cong tan, huong dan
toan cao » toan ban
toan tap » toan ban

You may be able to get more results by adjusting your search query.

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