Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
trinh vat » trinh van, trinh luat, sinh vat
ho chieu » theo chieu, hoc thieu, doi chieu
trinh va » trinh van, trinh ve, trinh vi
cong tan » cong tac, cong thanh, cong ty
cong san » cong tac
toan cao » toan ban, toan tap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ho chieu sach - hanh ((trinh va) OR (trinh vat)) nhung ((cong tan) OR (cong san)) toan cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho chieu sach - hanh ((trinh va) OR (trinh vat)) nhung ((cong tan) or (cong san)) toan cao~".
• Adding a wildcard symbol may retrieve word variants: ho chieu sach - hanh ((trinh va) OR (trinh vat)) nhung ((cong tan) or (cong san)) toan cao*.