Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
nhung cong » dung cong, thong cong, hang cong
hoc chieu » hoc thieu, ho chieu, hoc hien
trinh ban » trinh han, trinh dan, trinh bao
trinh san » trinh han, trinh quan, trinh toan
dan toan » dan than, manh toan, xuan toan
van toan » van tuan, van tan, van thanh

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 - hanh ((trinh ban) OR (trinh san)) nhung cong ((dan toan) OR (van toan)) tap~.
• Adding a wildcard symbol may retrieve word variants: hoc chieu sach - hanh ((trinh ban) or (trinh san)) nhung cong ((dan toan) or (van toan)) tap*.