Perhaps you should try some spelling variations:
thanh trung » thanh tung
theo chieu » theo tieu, ho chieu, theo chu
chieu sach » chinh sach, chiet tach, chieu sang
luong cong » dung cong, trong cong, cong cong
trung dai » truong dai, truong dao, trung tam
dai luong » dai cuong, dai duong, do luong
cong tan » cong tac, cong san, cong thanh
than cap » khan cap, thanh lap, thanh cac
khan ap » khan cap, han ap, khan dam

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 chieu sach - thanh trung dai luong cong tan ((than cap) OR (khan ap))~.
• Adding a wildcard symbol may retrieve word variants: theo chieu sach - thanh trung dai luong cong tan ((than cap) or (khan ap))*.