Perhaps you should try some spelling variations:
quan dung » quang dung, quan duong, qua dung
dung cong » dung trong
cau sach » hau sach, rau sach, khau sach
cao sach » co sach, ao sach, lao sach
hanh san » thanh san, khach san, thanh son
cong tan » cong tac, cong san, cong thanh
tan than » tan thanh, tan tran, ban than
than cau » toan cau, phan cau, than cap

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: theo ((cau sach) OR (cao sach)) - ((hanh san) OR (khach hang)) quan dung cong tan than cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((cau sach) OR (cao sach)) - ((hanh san) or (khach hang)) quan dung cong tan than cau~".
• Adding a wildcard symbol may retrieve word variants: theo ((cau sach) OR (cao sach)) - ((hanh san) or (khach hang)) quan dung cong tan than cau*.