Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
trinh quan » tinh quang, trinh luat
doi chieu » doc hieu, doi chi, ho chieu
long cong » luong cong, cong cong, tong cong
dung cong » dung trong
van van » van ban, tan van, san van
van dau » van dao, phan dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi chieu sach - hanh ((trinh quan) or (trinh han)) ((long cong) or (dung cong)) van van dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chieu sach - hanh ((trinh quan) OR (trinh han)) ((long cong) OR (dung cong)) van van dau.
• Adding a wildcard symbol may retrieve word variants: doi chieu sach - hanh ((trinh quan) or (trinh han)) ((long cong) or (dung cong)) van van dau*.