Perhaps you should try some spelling variations:
tang luan » dung luan
luan hang » luan nang, luan han, luan hung
theo thu » theo chu, theo tu, theo tieu
thu hang » thi hang, thuc hanh, thu huong
anh tang » anh bang, anh dang, anh nang
cong tac » cong ty
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: theo thu hang - anh tang luan hang ((cong san) or (cong tac)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo thu hang - anh tang luan hang ((cong san) OR (cong tac)) toan cau.
• Adding a wildcard symbol may retrieve word variants: theo thu hang - anh tang luan hang ((cong san) or (cong tac)) toan cau*.