If you click on a previous match, there will be a button on the screen titled "Analytical Data" - this will bring up a pop up with some tabs. You can use the information in here to identify lots of different things, and then watch the associated event in the game. I will often use this to see if there were specific players or areas of the pitch where passes weren't completed. Maybe someone isn't as good as I think, or maybe not as good as they think (they keep trying passes they don't have the capacity to pull of consistently). Maybe there's a striker who is meant to be the recipient of these passes, but he's too slow to get on the end of the them. Maybe our centre-backs are sending the ball long too frequently. And so on.
The inverse of this can be useful, too. Maybe most of the opposition's key passes were coming from a specific area of the pitch, and I need to think about changing a player, their role or instructions to address some form of defensive deficiency.