Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
doi chieu » doi chi, ho chieu, mot chieu
doc hieu » toc thieu, hoc thieu, hoc hien
van nang » van quang, van ban, van dong
dan toan » van toan, dan than, manh toan
toan cao » toan ban, toan tap
va dang » van dang, va nang, va lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chieu) or (doc hieu)) xanh - canh trinh ((va dang) or (van nang)) huong dan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (doc hieu)) xanh - canh trinh ((va dang) OR (van nang)) huong dan toan cao.
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) or (doc hieu)) xanh - canh trinh ((va dang) or (van nang)) huong dan toan cao*.