Delmiting search by child and parent nodes

I am trying to make my search fields only searchable on the current page in question and all of it's child pages. and only if they have children, so the home-index page has no children thus it will search the whole website.  (attached is a little example)
 However i am having some issues in doing so.
I used to be on Sitefinity 3.7 and this was accomplished rather easily, and i have since moved to sitefinity 6.2.

I have read the documentation for PagePipeNoIndex under the sitefinity blog post :
www.sitefinity.com/.../publishing_system_brief_walkthrough

however i have had no luck with that one. also i have tried following a different post  : www.sitefinity.com/.../set-start-page-for-search-index
also with no luck.
I have also made the bootstrapper to register the new pipe and unregister the default pipe, but that also got me no difference in my search results.

Hello Daniel,

For the moment, extending of the backend search is not available. In 3.7 this was achievable, but since then the search has a totally different implementation and this feature requires a lot of internal modifications.

I will add a feature request for some of our future releases to make easier extending the backend search.

Regards,
Vassil Vassilev
Telerik