If you are satisfied that you did all you could in your attempt to recover that deer, then I guess you are sure of what happened and nothing need more be done.

What color hair was it. If it was the brown outer hair, you must have hit solid. If it was the white under belly, then you might have just shot under it. These deer can go a long way before dropping blood. Especially if due to the close range that powerbelt entered, expanded, and then did not pass through. One hole just don't bleed as well as two holes.

All I will say is... I hunted with a friend that had the same thing basically happen to him. He shot, and looked most of the morning. Then he called me over. We found brown outer hair and no blood. He decided, he tracked it best he could. While upset with "missing" he finally decided to go home for the day as he worked later that early evening. I worked his stand for over four hours and found his deer later that afternoon almost three hundred yards from the stand. He had shot further back then he should. A liver shot I would have called it.

Perhaps you will have better luck in the next one you shoot at.