Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sach » chinh sach, chiet tach, chieu sang
hieu luat » hieu qua
trung cac » truong cac, trung cap, trong cac
cac thanh » bac thanh, cach nhanh, ban thanh
hieu luc » hieu qua
cong van » cong vang, cong san, song van
van toan » van tuan, van tan, van thanh
toan cao » toan ban, toan tap

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: doc ((((hieu luc) OR (hieu luat))) OR (chieu sach)) - thanh trung cac thanh cong van toan cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((((hieu luc) OR (hieu luat))) or (chieu sach)) - thanh trung cac thanh cong van toan cao~".
• Adding a wildcard symbol may retrieve word variants: doc ((((hieu luc) OR (hieu luat))) or (chieu sach)) - thanh trung cac thanh cong van toan cao*.