Trim or insulation cover

Hello there. Does any of that wool strips look worn or damaged? If so, you may need new wool pile weather-stripping, which will certainly bolster the insulation. You'll need to compare the size of the base and the height of the pile of your old wool pile with our selection here. See if any match what you need. The video below goes into more details. 

You also may want to give the tracks and rollers a look to make sure damage is not the cause of the door being mis-aligned. This guide here goes into maintenance for sliding glass doors.