Perhaps you should try some spelling variations:
nhung chong » nhung cong, nhung phong, nhung phuong
chieu sach » chinh sach, chiet tach, chieu sang
lanh tranh » canh tranh, lan tranh, hanh trinh
doc chieu » doc hieu, doi chieu, toc thieu
van toan » van tuan, van thanh, manh toan
van tan » van tuan, van ban, van tai

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 chieu sach - ((lanh tranh) OR (hanh chinh)) va nhung chong ((van toan) OR (van tan)) cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc chieu sach - ((lanh tranh) or (hanh chinh)) va nhung chong ((van toan) OR (van tan)) cao~".
• Adding a wildcard symbol may retrieve word variants: doc chieu sach - ((lanh tranh) or (hanh chinh)) va nhung chong ((van toan) OR (van tan)) cao*.