Thank you all for the help. Struck out today, but will be out looking again tomorrow morning. I am marking the trail with toilet paper so it is easy to follow and backtrack. Tomorrow my strategy will be to go to the fresh blood sign in the thicket and look for a new trail. The fresh blood stopped in the thicket. I marked it as the "last blood". There is a trail of old blood leaving from it, but not fresh. Maybe I missed the new trail.
It has now been 30 hours since the deer was hit. How long can a deer survive a single lung hit? Is it probable the deer is dead or alive? Thanks again.