Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
hanh dong » anh dong, ha dong
dong dung » dong duong, duong dung, cong dung
dung cong » dung trong
cong tan » cong tac, cong san, cong thanh
tan van » tran van, tang van, luan van
van dan » van ban, ban dan, van dao

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 (toc thieu)) tinh - hanh dong dung cong tan van dan ca~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (toc thieu)) tinh - hanh dong dung cong tan van dan ca.
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) or (toc thieu)) tinh - hanh dong dung cong tan van dan ca*.