Sure! Here are sentences using the requested phrases:
Come back: After studying abroad for a year, I can’t wait to come back home and see my family.
Come round: I hope you can come round to my place this weekend to watch the new movie together.
Come out: The new book by my favorite author is set to come out next month, and I’m really excited to read it.
Come across: While cleaning my room, I happened to come across an old photo album filled with memories from my childhood.