Research can be tricky because you need to plan. You must know what your topic is and what your stance is on that topic. You can then create a chart that has your thesis statement in one box, and your topics in three different boxes thereby as you research, you can put the information you find in those boxes. For example: Let's say you are researching the effects of smoking. Your thesis statement would say something like: Smoking is harmful for your health because it can stunt your growth, cause cancer, and cost several hundred dollars a year.
Then as you research, you would note supporting details (facts) for how is 1. stunts your growth, 2. causes cancer, and 3. costs money.
So....you should keep notes about your topics for your body paragraphs.