Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
hien hanh » dieu hanh
hanh tang » hanh trang, anh tang, hanh mang
hang cong » dang cong, hang nong, bang cong
dan toan » dan than, manh toan, xuan toan
van toan » van tuan, van tan, van thanh
tang va » trang va, tang van, thang va
va hang » van hang, va nang, va lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hien hanh) or (chieu sach)) - hanh tang va hang cong ((dan toan) or (van toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien hanh) OR (chieu sach)) - hanh tang va hang cong ((dan toan) OR (van toan)) cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((hien hanh) or (chieu sach)) - hanh tang va hang cong ((dan toan) or (van toan)) cau*.