Thunderbolt Display Daisy Chain Mini Displayport Monitor
I have connected the Mini Displayport into the back of the Thunderbolt
  Display and connected the Thunderbolt display into my Mac and the
  Samsung screen will not work.


Unfortunately, this will not work.  You cannot attach (daisy chain) another monitor off of the Thunderbolt port on a Thunderbolt display. It's a limitation of the monitor, not the MBA

From AppleInsider:  Apple clarifies Thunderbolt Display will not daisy chain Cinema Display


  However, users with an existing Mini DisplayPort external monitor will
  not be able to daisy chain the screen from the back of the new
  Thunderbolt Display, despite it being physically compatible with the
  port. Apple notes that "Mini DisplayPort displays will not light up if
  connected to the Thunderbolt port on an Apple Thunderbolt Display."