Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
hanh dang » hanh dong, anh dang, hanh dung
nang cong » nang song, dang cong, bang cong
ho chieu » theo chieu, hoc thieu, mot chieu
dang van » hoang van, hang va
van nang » van quang, van ban, van dong
cong dan » cong san, cong tan, huong dan
toan cao » toan ban
toan tap » toan ban

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 (doi chieu)) tinh - hanh dang van nang cong dan ((toan cao) or (toan tap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (doi chieu)) tinh - hanh dang van nang cong dan ((toan cao) OR (toan tap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) OR (doi chieu)) tinh - hanh dang van nang cong dan ((toan cao) or (toan tap))".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) OR (doi chieu)) tinh - hanh dang van nang cong dan ((toan cao) or (toan tap))*.