Do not continuously jump from one subject to another. Concentrate only on the working of your own mind. If we do not do this, we will only encounter Suffering and will be completely in Ignorance. Thinking of this person or that person only lead to the same thing. But if the thinking happens or arises in our mind and we stop it there, then that is wisdom.
Do not think about everything external. If we let our mind wander, Suffering will be with us. At the same time Ignorance will follow. But if thinking takes place in our mind, born in our mind, we must stop it there. This is wisdom which will stop Suffering and bring happiness without having to seek worldy wealth.