Perhaps you should try some spelling variations:
hanh tranh » canh tranh, hanh trang, lanh tranh
hanh trinh » canh tranh, hanh chinh
doi chieu » doi chi, ho chieu, mot chieu
dung cong » dung trong
doc hieu » toc thieu, hoc thieu, hoc hien
cong van » cong vang, cong san, song van
van toan » van tuan, van tan, van thanh
toan ban » van ban
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: ((doi chieu) or (doc hieu)) xanh - ((hanh tranh) OR (hanh trinh)) va dung cong van toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (doc hieu)) xanh - ((hanh tranh) OR (hanh trinh)) va dung cong van toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) or (doc hieu)) xanh - ((hanh tranh) OR (hanh trinh)) va dung cong van toan ban".
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) or (doc hieu)) xanh - ((hanh tranh) OR (hanh trinh)) va dung cong van toan ban*.