Moving from subtitles to native content: I feel like I’m missing the 'connective' tissue

I’m at the point where I can follow the gist of a Bosnian YouTube vlog, but I feel like I’m just guessing half the time. It’s the fast-paced, everyday speech where everyone seems to drop endings or use regional vocabulary I haven't seen in my textbooks. How do you guys bridge that gap? Should I be re-watching scenes, or is there a better way to pick up this natural, modern Bosnian flow?