Seems like the model has some kind of a USA centric worldview bias? Why would it consider flights to the USA, LA in particular? Was this where you were located when you did the query? That would be impressive :)
Pretty much everything in English now days has that tendency. It is quite annoying tbh. It is no longer a US centric world any more.
Levneletenkyzprahy.cz[1], Jaknaletenky.cz[2], Levneletenky.org[3] and Skyscanner.cz[4] all offer flights from Prague to London, with prices ranging from 490 Kč to 1 200 Kč depending on the season and airline[1][2][3][5].
490Kc/22USD - 1200Kc/54USD
Not sure why is exactly London specific, but it's for sure more useful than those expensive US flights.