Custom Tool : While using VSO REST api's I am unable to get the entire hierarchy within the project.

I am trying to query using visual studio online REST api's. When I run the following query

I receive a response with only 2 layers of children as in

project:OS

-> My queries

-> Shared queries

           ->Release Management

I am interested in querying the children folders of release Management too. How do I form my query to be able to access sub-children? Currently this query just returns the url and name etc. No children information is returned.