Perhaps you should try some spelling variations:
chieu sach » chinh sach, chieu sang, chieu xanh
hanh trang » thanh trung, canh tranh, hanh trinh
cua phuong » cuu phuong, cuc phuong, luan phuong
cua thong » cua thuong, cua khong, cua tong
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai toan
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chiet tach) OR (chieu sach)) - hanh trang ((cua thong) or (cua phuong)) cong tap toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chiet tach) OR (chieu sach)) - hanh trang ((cua thong) OR (cua phuong)) cong tap toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chiet tach) OR (chieu sach)) - hanh trang ((cua thong) or (cua phuong)) cong tap toan ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((chiet tach) OR (chieu sach)) - hanh trang ((cua thong) or (cua phuong)) cong tap toan ban*.