twitter search api - selecting only text not user

Question

if I want to search for q = 'dreamer' I would like to get only the tweets having the searched word (dreamer) and not the username having in their username the searched word. As you can see here when I searched for dreamer I got some tweets having in their text the world dreamer but also some tweets from username who have dreamer as a part of their username. How can I filter so I can only have the tweets having the researched word (and not users). Thank you