On the Home Screen, tap Sonos Radio and scroll down.

Or type what you’re looking for (like “funk” or “Colombia”) in the search box and on the results page, tap Sonos Radio at the top.

If you subscribe to a music service like Spotify, then add it as a Service and that will also bring up results when you search for artists or song titles.

Great! Thank you so much for the answer! Instead of a music service, ¿does Sonos include a service for search of artists or song titles? or is there any free music service? Thanks  

Sonos Radio is free (but ad supported) for every Sonos user. But you can’t search for individual songs as that is very much reserved for the music streamers. Many music streaming services offer a free tier, if you’re prepared to listen to ads all the time - and in some cases you can’t select a track, you can just listen to their curated playlists with the only facility being to skip a track.

(Below is a grid of free ad-supported music services you can add to Sonos aif you set up an account with the streaming service]. I don’t know if TuneIn Radio is supported on Sonos any more.)

Thank you so much. This info is very useful. I´ll try it.