Perhaps you should try some spelling variations:
thuong cong » thong cong, thuong con, thuong dong
manh trung » manh tung, thanh trung, manh hung
tam thuong » tai thuong, tam huong, pham thuong
hieu cac » hieu va, hieu van, vien cac
hieu luc » hieu luat, hieu qua
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.

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu cac) OR (hieu luc)) - manh trung tam thuong cong ((dan toan) OR (van than)) cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu cac) OR (hieu luc)) - manh trung tam thuong cong ((dan toan) or (van than)) cau~".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu cac) OR (hieu luc)) - manh trung tam thuong cong ((dan toan) or (van than)) cau*.