This is a matter of setting up the appropriate surfaces, volumes, or points. Most likely you should have a goal on them when solving already. Depending on what you are trying to do and how complex your analysis is, this can be a very difficult thing to explain in a forum. If you want to share more information about your analysis, people can try to help you, otherwise I would recommend contacting a reputable SOLIDWORKS VAR and taking the training for this product. It will pay itself back with increased productivity in no time.
PUT A SOLID BLOCK OR OTHER APPROPRIATE SHAPE IN THE MODEL SO YOU GET A SURFACE WHERE YOU WANT. THEN USE COMPONENT CONTROL AND DISABLE IT. THEN ASSIGN A GOAL TO THE SURFACE. IT HAS TO BE A SOLID COMPONENT. ADD AS MANY "SENSORS" AS YOU LIKE.