Crunches will strengthen the abs muscle area, but they cannot help get rid of the fat that lays across the abs, which is what is preventing the abs from being seen. You need to incorporate cardio into your routine on a regular basis to encourage the body to burn fat for fuel. Weight training programmes will also help in this area because muscle burns more calories than fat even when it is at rest. But cardio is the best for fat burn, and this will lead to the stomach fat also diminishing, so you'll be able to see those abs...never neglect cardio, and don't get caught up doing loads of abs exercises on a daily basis...it's best to do them every other day, because the muscle needs to recover and grow on its rest days. I do very little abs work but when the bodyfat is lower I can see my abs, so my weight training and cardio routine work brilliantly to burn the excess fat off the entire body. If I neglect to exercise then I gain more bodyfat...especially if I keep eating like a maniac, which I normally do 'cos I like food.