iTunes 11 allows you to integrate your cloud-based music, movie, and TV show purchases directly into your iTunes library, where you can easily download or stream anything in your purchase history. While you can disable this feature entirely if you don’t want to see any of your cloud-based purchases at all, you can also easily hide items individually.
Simply select the item from your iTunes in the Cloud library that you would like to hide, and delete it as if you were removing it from your local iTunes library. You’ll see a dialog box asking you to confirm whether or not you want to hide the item in iCloud. Select the Hide option, and the item will vanish from your library as if you had actually deleted it. Keep in mind, however, that this will also hide the purchased item from all of your devices that share the same iTunes Store account; you can un-hide any hidden purchases by logging into the iTunes Store and selecting your “Account Information” and looking for the “Hidden Purchases” section.