Custom Search not finding the related content in taxonomy

First of all, hello and thank you for providing all this data.

I have list of products assigned to sweet category.

I've set up a custom search block with the field and the dropdown list with my taxonomy tree with a depth of 20.

When i enter a search key (product) and hit submit on the child level.

And it displays me a page with all the results as expected, but when i try to use the dropdown list specifying root from my taxonomy tree, i get no results at all.

the url displaying: mywebsite/search/node/Product%20term%3A1

Any idea of what is happening?

Thanks