Perhaps you should try some spelling variations:
thanh trung » thanh tung
thieu xanh » chieu xanh, hieu manh, thien danh
thien anh » thien danh, tien anh, thien thanh
cua chong » cua chung, cua khong, cuu chong
cong tac » cong ty
tac toan » tap toan, tam toan, hach toan
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: hoc ((thieu xanh) OR (thien anh)) - thanh trung ((cua chong) OR (cua cong)) cong tac toan ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu xanh) OR (thien anh)) - thanh trung ((cua chong) or (cua cong)) cong tac toan ban~".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu xanh) OR (thien anh)) - thanh trung ((cua chong) or (cua cong)) cong tac toan ban*.