Include by categories or terms (restrict to category)
Restricting results to certain category/categories only
This section describes, how to restrict the post type results to a certain category, or to multiple categories.
Advanced options -> Exclude results panel
Go to the Advanced options -> Exclude results panel and scroll down until the Include posts.. option
Choose a taxonomy and the terms will load. Select the ones you need by dragging them to the left side of the box.
Save the options, done
Hiding posts (or any CPT) with no categories or terms
By default, selected post type objects which are not associated with any terms will appear in the results list.
If you whish to exclude them as well, then trun OFF the Show posts/CPM with empty taxonomy terms? option on the Frontend Search Settings -> Advanced panel:
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