Perhaps you should try some spelling variations:
thuong cong » thong cong, thuong con, thuong dong
van thuong » va thuong, van chuong, van phuong
nhieu tang » chieu sang, nhiet nang
hieu lang » chieu sang, hieu quang, hieu van
hanh tran » hanh trang, thanh tran, hanh tram
tran van » luan van
dan toan » van toan, manh toan, xuan toan
dan than » dan chan, ban than, van than

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 lang) OR (nhieu tang)) - hanh tran van thuong cong ((dan toan) OR (dan than)) ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu lang) OR (nhieu tang)) - hanh tran van thuong cong ((dan toan) or (dan than)) ban~".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu lang) OR (nhieu tang)) - hanh tran van thuong cong ((dan toan) or (dan than)) ban*.