Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
nhieu tang » chieu sang, nhiet nang
hieu lang » chieu sang, hieu quang, hieu van
hanh tang » hanh trang, anh tang, hanh mang
hang cong » dang cong, hang nong, bang cong
cong san » cong tac
san toan » van toan, dan toan, manh toan
toan ban » van ban
tang va » trang va, tang van, thang va
va hang » van hang, 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: theo ((chieu sach) or (((hieu lang) OR (nhieu tang)))) - hanh tang va hang cong san toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((chieu sach) OR (((hieu lang) OR (nhieu tang)))) - hanh tang va hang cong san toan ban*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chieu sach) or (((hieu lang) OR (nhieu tang)))) - hanh tang va hang cong san toan ban*".