I jailbroke my iPad from this download: [ Register or Signin to view external links. ]

And it successfully downloaded on the 5.0.1 operating system. My cydia works fine from what I can see, but my search doesn't work, as in nothing comes up when I search a word. Neither do any of my tools or themes. Whenever I click on a tool or theme is gives me an error message. Is says

Note: Cannot Locate Package. This package com.saurik.iphone.fid cannot be found in your current sources. I might recommend installing more sources.
This issue may also be caused by a number of other factors. the most common one is that your package catalog is out of date. To manually refresh, click the Refresh button on the Changes tab. This package may simply no longer exist. (which it does) It is also possible you are using an old firmware version: users should attempt to remain reasonably up to date with Apple's firmware releases.

It does this ^ every time I tap on anything in cydia.

It isn't an old firmware because its 5.0.1
I don't understand the problem, and if anyone can help me that would be greatly appreciated.