Perhaps you should try some spelling variations:
chieu sach » chinh sach, chieu sang, chieu xanh
hanh trinh » canh tranh, hanh chinh
thong cong » trong cong, tong cong, thong thong
trinh cua » tinh cua, trinh luat, trinh quan
cua thong » cua thuong, cua khong, cua tong
van thanh » ban thanh, van tuan
van than » van thang, van tuan, van phan

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