Your first port of call in a situation like this should be your tutors. They should be helping you formulate valid CCQs. The next time your tutors criticise an inadequate CCQ, ask him/her what s/he would have asked. Don't be shy about asking - that's part of the tutor's job.
You might find this helpful: http://www.eslbase.com/tefl-a-z/concept-questions

English Teacher