Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
dung cong » dung trong
van thanh » ban thanh, van tuan
thanh ban » thanh san, thanh van, thanh bac
trinh vi » trinh ve, trinh viet, trinh van
trinh va » trinh van, trinh vat, trinh ve
cong van » cong vang, cong san, song van

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((dieu hanh) or (chieu sach)) - canh ((trinh vi) OR (trinh va)) dung cong van thanh ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((dieu hanh) OR (chieu sach)) - canh ((trinh vi) OR (trinh va)) dung cong van thanh ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((dieu hanh) or (chieu sach)) - canh ((trinh vi) OR (trinh va)) dung cong van thanh ban".
• Adding a wildcard symbol may retrieve word variants: ho ((dieu hanh) or (chieu sach)) - canh ((trinh vi) OR (trinh va)) dung cong van thanh ban*.