Perhaps you should try some spelling variations:
hanh trinh » canh tranh
dung cong » dung trong
ho chieu » theo chieu, hoc thieu, doi chieu
doc hieu » toc thieu, hoc thieu, hoc hien
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai toan
toan tap » toan ban
va dung » van dung, va duong, vat dung

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 (doc hieu)) xanh - ((hanh trinh) or (hanh chinh)) va dung cong tap toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (doc hieu)) xanh - ((hanh trinh) OR (hanh chinh)) va dung cong tap toan tap.
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (doc hieu)) xanh - ((hanh trinh) or (hanh chinh)) va dung cong tap toan tap*.