Please read the links I posted above. Also read http://web.stanford.edu/~boyd/papers/pdf/cvx_ccv.pdf .
Here are some CVX examples of DC Programming http://web.stanford.edu/~boyd/software/cvx_ccv_examples/ (called onvex-concave procedure).
As you can see in my response to your question Can CVX solve this optimization problem?Can you help me? , the key requirement for applicability of DC Programming is that there is a difference of convex functions (or concave functions). And for use of CVX, also the requirement that the convex optimization problem arising from fixing the non-convex “side” can be entered into CVX in compliance with its DCP rules.