Perhaps you should try some spelling variations:
canh trinh » canh tranh, hanh trinh, canh tinh
hoc thieu » toc thieu, hoc hien
dung cong » dung trong
ho chieu » theo chieu, doi chieu, mot chieu
trinh va » trinh van, trinh vat, trinh ve
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan cau » toan cao, toan ban, toan tap
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 (hoc thieu))) or (doi khi)) xanh - canh trinh va dung cong san toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((ho chieu) OR (hoc thieu))) OR (doi khi)) xanh - canh trinh va dung cong san toan cau.
• Adding a wildcard symbol may retrieve word variants: ((((ho chieu) or (hoc thieu))) or (doi khi)) xanh - canh trinh va dung cong san toan cau*.