firebase deep query web

I need to get a deep query from firebase in a web platform...

I have the following:

• Content
  • User ID 1
    • Time Stamp 1
      • userField 1
      • userField 2
      • userField 3
      • userField 4
    • Time Stamp 2
      • userField 1
      • userField 2
      • userField 3
      • userField 4
  • User ID 2
    • Time Stamp 1
      • userField 1
      • userField 2
      • userField 3
      • userField 4
    • Time Stamp 2
      • userField 1
      • userField 2
      • userField 3
      • userField 4

I can call the following: var rootRef = firebase.database().ref().child("Content").child("User ID 1")

Which Doesn't help as I need to get all users information into one table...

and if I use the following: var rootRef = firebase.database().ref().child("Content") nothing calls?

I understand that firebase uses a shallow call, but how do I get around it?

Any suggestions? Thanks kindly for your help...