Perhaps you should try some spelling variations:
chiet tach » chieu sach
hieu lang » chieu sang, hieu quang, nhieu tang
hanh tran » hanh trang, thanh tran, hanh tram
tuan cong » thuan cong, luan cong, tran cong
manh toan » thanh toan, tinh toan
tran van » luan van
van tuan » van quan, 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: ho ((chiet tach) OR (hieu lang)) - hanh tran van tuan cong ((manh toan) OR (anh tuan)) cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chiet tach) or (hieu lang)) - hanh tran van tuan cong ((manh toan) OR (anh tuan)) cau~".
• Adding a wildcard symbol may retrieve word variants: ho ((chiet tach) or (hieu lang)) - hanh tran van tuan cong ((manh toan) OR (anh tuan)) cau*.