2. So, to uncheck the tags just use the “tick” signs next to them: https://i.imgur.com/zIK1vtN.png
I've unchecked all of them for you.
1. The issue here is that in case of tag and category (or other taxonomy term) filters are connected with an AND logic all the times. It's a performance related thing, due to the usually large amount of tags per site.
Therefore I've changed one thing on the Frontend Search settings -> Advanced panel: https://i.imgur.com/HqzomQw.png
This way the search must match at least one of the categories and also match one of the tags at the same time – but in case of multiple categories and tags, only one of the selected is enough from each group. So the intersection of the results of the matching categories and the matching tags is the final result set.Best,
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