Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
doi chieu » doc hieu, doi chi, ho chieu
trung hoc » trung quoc
dung cong » dung trong
cong lang » cong vang, cong luong, cong quang
lang toan » dang toan, lang thang, lang thanh
trung va » truong va, trang va, trung ha
toan cao » toan ban, toan tap

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 - thanh ((trung va) or (trung hoc)) dung cong lang toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chieu sach - thanh ((trung va) OR (trung hoc)) dung cong lang toan cao*.