Hi @Amalie1
When you look at the Power Automate Flow for "Search Documents" and you look at the Runs, what do you see?
Are there any results?
This shows no results:

Or does it look like this with Results?

The example you are looking at is pretty complicated as far as what it is accomplishing.
The formula you have in the Power App is what the video shows. You need to check your Power Automate Flow to ensure it is working correctly.
I was not able to get the "Path" part of the SharePoint Search REST API to work correctly, but that may just be me. I I simplified the Uri in the "Send an HTTP request to SharePoint" to:
/_api/search/query?querytext=%27*%27
where "*" was the Search Text I was passing to at least get results.
From Reza's video, click the "...more" link to additional information:

Here shows the formulas to use. You can also subscribe to his channel for a fee and get the complete source code (if needed).
-Mark
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