Perhaps you should try some spelling variations:
tranh tran » thanh tran, tranh toan, tranh tren
thi chieu » thi chien, thi hieu, theo chieu
tran dung » tran dang, tran hung, tran quang
dung cong » dung trong
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 ban » van ban
doi chi » doi khi

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((((thi chieu) or (doc hieu))) or (doi chi)) xanh - canh tranh tran dung cong tap toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((thi chieu) OR (doc hieu))) OR (doi chi)) xanh - canh tranh tran dung cong tap toan ban.
• Adding a wildcard symbol may retrieve word variants: ((((thi chieu) or (doc hieu))) or (doi chi)) xanh - canh tranh tran dung cong tap toan ban*.