Perhaps you should try some spelling variations:
quyen tai » xuyen tai, nguyen tai, truyen tai
cong cong » cong dong, trong cong, dung cong
cac thoi » cac toi, cac hop, cac tro
cac khu » cac thu, cac khoi, cac kieu
y thuc » ty thuc, y thuoc, a thuc
_ thuc » _ thu
ban le » ban ve
y thu » ly thu, ky thu, _ thu

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

• Performing a fuzzy search may retrieve terms with similar spellings: quyen tai ((cac khu) or (cac thoi)) đe co ban le ((y thu) or (((y thuc) OR (_ thuc)))) cong cong~.
• If you are trying to use Boolean operators, they must be ALL CAPS: quyen tai ((cac khu) OR (cac thoi)) đe co ban le ((y thu) OR (((y thuc) OR (_ thuc)))) cong cong.
• The words AND, OR and NOT may confuse the search; try adding quotes: "quyen tai ((cac khu) or (cac thoi)) đe co ban le ((y thu) or (((y thuc) OR (_ thuc)))) cong cong".
• Adding a wildcard symbol may retrieve word variants: quyen tai ((cac khu) or (cac thoi)) đe co ban le ((y thu) or (((y thuc) OR (_ thuc)))) cong cong*.