Perhaps you should try some spelling variations:
chieu sach » chinh sach, chieu sang, chieu xanh
doanh hoan » doanh doanh, doanh khoa, doanh nhan
nhung cong » dung cong, thong cong, hang cong
san toan » dan toan, manh toan, xuan toan
van toan » van tuan, van tan, van thanh
hoan va » khoan va, hoang va, doan va

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: hoc ((chieu sach) OR (chiet tach)) - doanh hoan va nhung cong ((san toan) OR (van toan)) ban~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sach) OR (chiet tach)) - doanh hoan va nhung cong ((san toan) or (van toan)) ban~".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sach) OR (chiet tach)) - doanh hoan va nhung cong ((san toan) or (van toan)) ban*.