In Column-View mode, a two-finger swipe forward will "push" you to the relevant content as if you clicked on it. The opposite direction two-finger swipe will "pop" you back. The direction adheres to your current scrolling settings as configured in System Preferences > Mouse/Trackpad > Scrolling > Scroll direction
While in the process of making a two-finger swipe, arrow indicators will appear in the Flume main window indicating the direction you are about to move in.