Laptop is always over heated

Hi! My dell latitude 13 is always over heated in summers due to excessive use. But I cannot minimize the usage of laptop because almost all of my work is related to computer. So I bought this cooling fan for my laptop and heard that it would minimize the heating process. Cooling fan is much like a small table on which you place your laptop and connect your laptop with it via USB. The problem is that even after using the cooling fan, laptop is still over heated and sometimes it restarts automatically due to over heating which results in data loss sometimes.