Slashfilm has all the details on deleted scenes that we should see on the future blu-ray release of The Last Jedi.
Perhaps the most notable of the scenes takes place on Ahch-To. Rey sees boats arriving at the island, with bonfires on the beaches. Luke tells her that the visitors are bandits that repeatedly come to the island to plunder and kill the caretakers. Rey wants to help, but Luke tells her the Jedi way is to basically let nature take its course, presumably also teaching her a similar lesson that he learned when he rushed off to face Vader. Rey nevertheless runs off to help (which we see briefly in one of the trailers) only to find that the "bandits" are actually the caretakers' husbands arriving from their fishing trips, and the bonfires are part of a celebratory party, in which even Chewie and R2 are participating. Rey is distraught, and returns to unload on Luke. According to the article, the scene was cut because it made Luke out to be too much of a jerk.
Other items cut from the movie include bits from Canto Bight (thankfully), Finn and Phasma's showdown (actually could have been cool), and some lines that develop romantic tension between Rose-Finn-Rey. Also, the dynamic between Holdo and Poe was altered, because supposedly Holdo came off as too much of a jerk, which would have made it more difficult for audiences to get behind the character later on.