A so called plumber left a cement buildup in my PVC shower drain, wondered why it was so slow draining. I have chipped out what I could at the flange but fished out a large chunk from the bend. Now I am concerned about what I can't get to. What can I use to check out further down? It is still slow draining and I have put Drano and other product in it so don't think it is the normal problems.

Stop with the Drano, it won't work on cement and will make other repairs dangerous. Call the plumber back and tell him his install was faulty. He should fix it at no charge, if not report him to your building department

Thanks for the advice. It's not possible to get the plumber back so guess I'll have to go elsewhere for help.

Try a snake with a spear tip. You may or may not be able to break up any remaining cement, which I would assume is thin set material or a sand mix from building the shower base. If you can break the cement up you should be able to get it out with a shop vacuum.
You shouldn't have any cement beyond the bottom of the trap.