Nutrition for gain lean muscle mass during strength training?

[confusedyoungmale]

I am not gaining any weight in fact I keep losing weight along with the fat around my waiste. One of my biggest concern is I can see my ribs when I inhale and exhale and I don't want to lose abdominal muscle my getting too much around around the obliques and other muscles. I have 3 servings of meat, 7 servings of vegetables, 2 servings of wheat bread, and milk almost every meal. I have 5 meals a day. To get the rest of my protein I eat nuts, beans, greek yogurt, and other dairy products such as cottage cheese. I am going to finish using my protein whey and not buy anymore because I have been using it for six moths and have been greatly disappointed in it. What should I do to gain muscle mass while not gaining any fat in the mid section so I can develop my six pack abs? I want to keep gettting strong and look great as well. I don't want to look like a model or a body builder, but I would still like to look sexy and feel strong and healthy in the mean time. I am not going to buy anymore supplments either because it is a wast of money and I am on a low income budget. Please just give me advise on nutrition only and not supplements or workout routines. Thanks for your incent and helping reach my goal.