My Ipod isn't syncing new music?

So, ipod 4gen. I recently got a new laptop and imported a couple CDs onto the Itunes. My Ipod used to be synced to my old Itunes, but I swtiched it to this computer. But now it's not syncing to the music on this laptop. I click sync and it says the sync is successful, but when I check the music from the CDs aren't there. What can I do to get the music on my Ipod?