At the App Store, go to your Purchases tab. Then, press the bottom leftmost button (shows your Apple ID). When you get the pop up, select the option to "View Apple ID." You'll have to put in your password and then you'll get another pop up. Somewhere in that popup is a line titled "Hidden Pruchases." pressing that line opens a page so you can view all your hidden purchases. There will be a button next to each where that you can press to unhide.
Hope this helps. Holler if you need more assistance.
Marilyn