What's actual batch volume vs target batch volume? If you're brewing 5 gallon batches and ending up with 6 gallons, then yeah, you're going to be a bit shy.
What's the recipe source? And what's the efficiency of the recipe? If you're using someone else's recipe, and it's set at 85 or 90% efficiency, and you're getting 65% efficiency, that'll explain at least a chunk of it. Most recipes from common sources seem to be set 70-75%, so if you're getting lower it shouldn't be too far off unless there's a bigger problem.
I would also look to crush first. If you're using store crush, buy yourself a mill. And then tighten it down from the factory setting. My Barley Crusher mill came preset at 0.038", if I recall correctly, and I adjusted it down to 0.032".
Sparging method is worth looking at too. If you're fly sparging and doing it fast, slow down. If you're batch sparging, make sure you're not wasting a bunch of sugars in extra sparge runnings. Especially if you're fly sparging, make sure your MLT isn't getting any channeling. If you're doing BIAB and no sparge, you might try sparging.
Make sure your sparge water is a high enough temp- you want the grain bed to be in the 168-ish range. If it's too low, sugars aren't as soluble. I batch sparge, and if I do a mash-out first, then sparge, I get a few extra points of efficiency.