Perhaps you should try some spelling variations:
kinh sach » sinh sach, dinh sach, tinh sach
hoc kinh » hoc sinh, luoc kinh
trung va » truong va, trang va, trung ha
cong dan » cong san, huong dan, cong dong
cong tan » cong tac, cong san, cong thanh
than cao » toan cao, thai cao, than cap
tung va » tuong va, dung va, vung va

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc kinh sach - thanh ((tung va) or (trung va)) hang ((cong dan) OR (cong tan)) than cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc kinh sach - thanh ((tung va) OR (trung va)) hang ((cong dan) OR (cong tan)) than cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc kinh sach - thanh ((tung va) or (trung va)) hang ((cong dan) OR (cong tan)) than cao".
• Adding a wildcard symbol may retrieve word variants: hoc kinh sach - thanh ((tung va) or (trung va)) hang ((cong dan) OR (cong tan)) than cao*.