Perhaps you should try some spelling variations:
quyen tai » xuyen tai, nguyen tai, truyen tai
cong cong » trong cong, dung cong, dang cong
tai cac » tai cuc
cac chu » cac thu, cac che, cac khu
co bang » cao bang, con bang, co ban
bang ly » hang ly
ky thu » ly thu, ky thi, ky thuat
ly ky » ly y
dong » dung

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 chu đe co bang ly ky thu ((cong cong) OR (cong dong))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "quyen tai cac chu đe co bang ly ky thu ((cong cong) OR (cong dong))*".