Perhaps you should try some spelling variations:
chi sach » chinh sach, chieu sach, co sach
anh tang » anh bang, anh dang, anh nang
cong san » cong tac
cong tan » cong tac, cong thanh, cong ty
than cau » toan cau, phan cau, than cap
doi chi » doi khi
tang va » trang va, tang van, thang va

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi chi sach - anh tang va nhung ((((huong dan) or (cong san))) or (cong tan)) than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chi sach - anh tang va nhung ((((huong dan) OR (cong san))) OR (cong tan)) than cau.
• Adding a wildcard symbol may retrieve word variants: doi chi sach - anh tang va nhung ((((huong dan) or (cong san))) or (cong tan)) than cau*.