Perhaps you should try some spelling variations:
quyen tap » tuyen tap, luyen tap, quyen cap
thai cong » tai cong, thanh cong, thai son
trac thoi » tran thi, cac thoi, rac thai
tap trac » tap toan
thi cong » tai cong, thien cong
ve ky » va ky, ke ky
ke y » ke ky, ke o
ve _ » va _

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

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