Perhaps you should try some spelling variations:
thanh tung » thanh cong
hieu xanh » chieu xanh, hieu manh, hieu nganh
doc hieu » toc thieu, hoc thieu, hoc hien
tung cua » trung cua, tuong cua, dung cua
cong tac » cong ty
than ban » thanh ban, than man, nhuan ban
toan ban » van 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 - thanh tung cua cong ((cong tac) OR (cong san)) ((than ban) OR (toan ban))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu xanh - thanh tung cua cong ((cong tac) or (cong san)) ((than ban) OR (toan ban))~".
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - thanh tung cua cong ((cong tac) or (cong san)) ((than ban) OR (toan ban))*.