Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
ho chieu » theo chieu, hoc thieu, mot chieu
cua bang » chua bang, cua ban, cua dang
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai toan
toan cao » toan ban, toan tap
chuc » thuc, chu, chua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho chieu) or (doi chieu)) sach - canh tranh ((cua bang) or (chuc nang)) cong tap toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (doi chieu)) sach - canh tranh ((cua bang) OR (chuc nang)) cong tap toan cao.
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (doi chieu)) sach - canh tranh ((cua bang) or (chuc nang)) cong tap toan cao*.