Perhaps you should try some spelling variations:
quyen cach » quyen sach, quyen anh
quyen cap » huyen cao, quyen con, quyen cua
cong cong » cong dong, trong cong, dung cong
cac che » cac he, cac chien, cac chat
y thuc » ty thuc, y thuoc, a thuc
_ thuc » _ thu
ban ve » ban va
y thu » ly thu, ky thu, _ thu

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((quyen cap) OR (quyen cach)) cac che đe co ban ve ((((y thu) OR (y thuc))) OR (_ thuc)) cong cong~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((quyen cap) or (quyen cach)) cac che đe co ban ve ((((y thu) OR (y thuc))) or (_ thuc)) cong cong~".
• Adding a wildcard symbol may retrieve word variants: ((quyen cap) or (quyen cach)) cac che đe co ban ve ((((y thu) OR (y thuc))) or (_ thuc)) cong cong*.