Hello FeatherInTheWind,
Thanks for reaching out through the Apple Support Communities about that situation with searching in the YouTube app on your Apple TV.
Is your Apple TV all up-to-date? Update Apple TV software
Does that persist after removing and reinstalling the YouTube app? Customize the Apple TV Home screen covers how to delete an app, for reference.
Should that still continue, and if it only happens with the YouTube app, you’ll want to reach out to YouTube to get further assistance. They’d be in the best position to assist with further troubleshooting their particular app. You can reach out to them here: YouTube Help
Take care.