So my shiny Scraggy was in the Dream World for almost 2 months, and she didn't meet any Pokemon!!
Why didn't she meet any Pokemon!?
to meet pokemon you have to go to the island of dreams where you get to travel to ten paths in various areas where you can meet pokemon and play a minigame to befriend them and if you win after ten moves you reach the tree of dreams where you can sacrifice a berry for only one pokemon from those you befriended.
for more information go to: http://www.serebii.net/blackwhite/dreamworld.shtml