Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
chat nhung » chat ngung, thuat nhung, cua nhung
nhung cong » dung cong, thong cong, hang cong
doi chieu » doc hieu, doi chi, ho chieu
canh tinh » hanh tinh, manh tinh, canh tranh
bai toan » bai tap
tam than » ban than
tap toan » tap doan, tap quan

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi chieu sach - canh tinh chat nhung cong ((((bai toan) or (tam than))) or (tap toan)) tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chieu sach - canh tinh chat nhung cong ((((bai toan) OR (tam than))) OR (tap toan)) tap.
• Adding a wildcard symbol may retrieve word variants: doi chieu sach - canh tinh chat nhung cong ((((bai toan) or (tam than))) or (tap toan)) tap*.