Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu sang
hieu quang » thieu quang, hieu quan, hieu qua
hanh trang » thanh trung, canh tranh, minh trang
hanh trinh » canh tranh, hanh chinh
cong cong » cong dong, trong cong, dung cong
cong dan » cong san, cong tan, huong dan
dan than » dan chan, ban than, van than
than cao » toan cao, thai cao, than cap

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