Drano/Liquid Plumr equivalent in Germany (with German name)
 

The subject line should be self-explanatory. I just need to know what to look for in Germany to find something to clear out a clogged shower drain. Thanks!

The subject line is not at all self-explanatory to us Germans who do not know the English/American brands...

"Abflussreiniger", "Rohrreiniger" are keywords to look for at the drug store. There are various brands. Depends if you want a strong chemical (handle with care), a milder organic version, or if environment-friendly mechanical measures will do (Saugglocke/Pümpel).
If you google "Abflusssreiniger" and open the page with the photos, you get to see the full assortment.

I use bleach at home. It's much cheaper and does a better job.