Any suggestion on how to weight without bouncing back??

I have been to LWM, Expression, took Bio Slim and lastly jogging thrice aday but I dont seem to shed any kilos... I even monitor my calories intake bit still on vain..

I thought of taking slimming pills or Herbalife but worried my weight lost will be in vain...

Anyone got a better suggestion or experience.. I need to lose 15kg in order to get back my pre-pregnancy weight..Hav been trying past 2 yrs but all fail..