Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
canh manh » lanh manh, canh tranh, van manh
bang cong » dang cong, bang song, hang cong
ho chieu » theo chieu, hoc thieu, mot chieu
cua bang » chua bang, cua ban, cua dang
cong tac » cong ty
tac toan » tap toan, tam toan, hach toan
toan cau » toan cao, toan ban, toan tap

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)) xanh - ((canh manh) or (cach mang)) cua bang cong tac toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (doi chieu)) xanh - ((canh manh) OR (cach mang)) cua bang cong tac toan cau.
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (doi chieu)) xanh - ((canh manh) or (cach mang)) cua bang cong tac toan cau*.