Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
trinh vatn » trinh van, trinh han, trinh san
trinh vat » trinh van, trinh luat, sinh vat
hang cong » dang cong, hang nong, bang cong
ho chieu » theo chieu, hoc thieu, doi chieu
cong dan » cong san, cong tan, huong dan
toan cau » toan ban, toan tap, toan tai
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 vat) OR (trinh vatn)) hang cong dan ((toan cau) OR (toan cao))~.
• Adding a wildcard symbol may retrieve word variants: ho chieu sach - hanh ((trinh vat) or (trinh vatn)) hang cong dan ((toan cau) or (toan cao))*.