Hi,
The issue with the magnifier is that you have enalbed the compact search box layout but it’s implemented incorrectly. If you turn it off, it will resolve the issue.
1. Okay, for that you want to disable the live search trigger on typing here. Then set the magnifier and return actions to trigger the live search.
2. In case you are choosing individual categories to display, you can set the checkbox states here. Make sure the settings are also visible as a block.