Mavericks won't let me use my second display as a pallets display
I have 2 monitors (displays), 1 for main app (such as Photoshop) and the other for its pallets (so I have more real estate to edit photos, etc. on the main display), but Mavericks won't let me do that. I dragged my pallets to the 2nd display, but when I change Spaces (using command and right or left arrow), and come back to the Photoshop space, the pallets are back on the main display. I.E. it is treating each display with it's own "space", so I would for ex. I would have had 4 spaces with both screens, now it is treating it like 8 separate spaces, 4 on each display. I want both displays to act as one very large display, with each 'space' I create. Any help how I can do this in Mavericks?
MacBook Pro, OS X Mavericks (10.9.2)