The law of attraction does not distinguish between our good and bad thoughts. We can attract things that we don't want as easily as we attract things that we want by thinking about them a lot. When we attract the experiences we want, it is considered deliberate attraction, while attracting experiences that we don't want is nondeliberate.
There are three steps to deliberately attracting what you want: clearly identifying what you want, focusing your thoughts on it and allowing it to manifest in your life.
In order to attract something that you want in your life, you must identify it first. We are often so busy thinking and talking about the things that we don't want that we are not clear about exactly what we do want.
The law of attraction says that when we give something we want positive attention, we create positive vibrations that make it easier to manifest our desire.
When we allow something into our lives, we are not giving it negative attention. Negative thoughts can come between us and the things that we want by creating a negative vibration.