Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, cong tan
chieu sach » chinh sach, chiet tach, chieu sang
hieu lang » chieu sang, hieu quang, nhieu tang
va trong » va truong, va tuong, va trung
va thong » va thuong, va phuong, he thong
cong san » cong tac
san toan » van toan, dan toan, manh toan
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: doi ((chieu sach) OR (hieu lang)) - cong thanh ((va trong) OR (va thong)) cong san toan cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((chieu sach) or (hieu lang)) - cong thanh ((va trong) OR (va thong)) cong san toan cao~".
• Adding a wildcard symbol may retrieve word variants: doi ((chieu sach) or (hieu lang)) - cong thanh ((va trong) OR (va thong)) cong san toan cao*.