Plugin doesn’t work

Hi. I just installed this plugin and generated a Search and placed it on a sidebar widget.

I used a field to search by Tags and another one to search by Category.

It doesn’t matter what I choose, I get no results. If I select ALL categories and any tag, doesn’t show any tag even though there are many posts with that tag. Any search I do, gives no results.

Is this plugin working with WordPress 4.7? do I have to activate jetpack or something?