Stop treating the composition as a work that requires creativity and the arrival of muses. I would ask for from teachers, but here is another option, and I want to consider it. The composition is a detailed answer to a rather broad question, which decomposes into several simpler ones. So do this: make a plan. Those. just lay out the topic on small issues. The more you can come up with such components - the more will be the composition. Then you answer yourself out loud “in a normal way” - i.e. so how would you reply to a friend. This is necessary in order to form an answer in your head - so it will then be easier to translate it into a decent written genre. Further to each of your answers you ask a question - “what do you prove?” This means that the answer to the question must be confirmed by facts from the text.