Video thumbnail?

Hello there,

when I make post with embed video I can’t see video like featured image. Is it possible to do this?

Example:
my website https://www.skateframe.cz (not ready at all, just testing)
look at the post “Tohle je video”. This post include embed video, when I click on the post, I can see it. But, there is no thumbnail or “little” video jako featured image..

I hope, you understand me :))

Thanks!