Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
hieu quang » thieu quang, hieu quan, hieu qua
thanh cung » thanh cuong, thanh cong, thanh tung
nhung cong » dung cong, thong cong, hang cong
cap nhung » cam nhung, vap nhung, dap nhung
cung cap » trung cap
cong tan » cong tac, cong san, cong thanh

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

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