Thumbnail

Hello,
we need show Thumbnail for Events/Akce. I did not find where we can add it.
We dont have Hide thumbnails in Settings.
Is possible you will help us?

Here we find it: https://www.rockandpop.eu/udalosti/
Problem is here, in right sidebar: https://www.rockandpop.eu/homepage-v2/

Thank you.

The page I need help with: [log in to see the link]