Perhaps you should try some spelling variations:
chieu sach » chiet tach, chieu sang, chieu xanh
hanh trang » thanh trung, canh tranh, minh trang
hanh trinh » canh tranh, hanh chinh
nhung cong » dung cong, thong cong, hang cong
gian bana » gian ban, gian dan, gian lang
cong dan » cong san, cong tan, huong dan

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chieu sach) OR (chinh sach)) - ((hanh trang) or (hanh trinh)) va nhung cong dan gian bana~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sach) OR (chinh sach)) - ((hanh trang) OR (hanh trinh)) va nhung cong dan gian bana.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sach) OR (chinh sach)) - ((hanh trang) or (hanh trinh)) va nhung cong dan gian bana".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sach) OR (chinh sach)) - ((hanh trang) or (hanh trinh)) va nhung cong dan gian bana*.