Do not download useless thoughts in your mind. Do not make your mind heavy with sorrowful thoughts, nor with thoughts that sound "interesting."
"I have the right to do anything," you say, but not everything is beneficial. "I have the right to do anything," but not everything is constructive. 1 Corinthians 10:23.
There was a monk, named Heronimos. He once said that if a river is clean and peaceful even a small needle can be seen at the bottom. We are just like that. If your minds are filled with the memory of Jesus and His words, with His help you will achieve such a peace that in that peacefulness you can see the needles inside your soul that harm you and cause sorrow. It is then that you will seeing them have the desire to take them out of of your soul and mind.
After that your soul won't be filled with hopeless sorrow and concerns of this world.