Perhaps you should try some spelling variations:
luyen tap » tuyen tap
luyen thi » nguyen thi
cong cong » cong dong, trong cong, dung cong
cac che » cac he, cac chien, cac chat
cac khu » cac thu, cac khoi, cac kieu
te cong » tai cong, thi cong, thu cong
ve ly » ve li, ve y, de ly
ve ky » va ky, ke ky

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

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