Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
tranh cua » doanh cua, manh cua
trong tap » trong thap, tong tap, trong tan
ho chieu » theo chieu, hoc thieu, mot chieu
cua dung » cua dang, cua dong, qua dung
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: ((doi chieu) or (ho chieu)) sach - canh tranh cua dung trong tap toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (ho chieu)) sach - canh tranh cua dung trong tap toan ban.
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) or (ho chieu)) sach - canh tranh cua dung trong tap toan ban*.