Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sach » chinh sach, chiet tach, chieu sang
hieu lang » chieu sang, hieu quang, nhieu tang
trung cua » truong cua, trung tuan, trung cap
cua nhung » va nhung
cong tan » cong tac, cong thanh, cong ty
cong san » cong tac
tran tap » toan tap, tran tan, tran tuan

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: theo ((chieu sach) or (hieu lang)) - thanh trung cua nhung ((cong tan) OR (cong san)) tran tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chieu sach) OR (hieu lang)) - thanh trung cua nhung ((cong tan) OR (cong san)) tran tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chieu sach) or (hieu lang)) - thanh trung cua nhung ((cong tan) OR (cong san)) tran tap".
• Adding a wildcard symbol may retrieve word variants: theo ((chieu sach) or (hieu lang)) - thanh trung cua nhung ((cong tan) OR (cong san)) tran tap*.