Search Algorithm

Hi everyone,

I would like to understand how the search algorithm work. I understand it is decentralised but I do not know how?
Do you know if there is some documentation or paper describing this algo?
Is there other tools that are using this search algo or is is closed to only tribler users?

Kind regards,

After some digging I found this doc but it is still not very clear how it works or on what principle/paper this Content Search is based on.