typo fix for keywords

Typo fix from: 18F/foia-hub/issues/362

Doesn't pull up FDA, but still makes more sense. 

![screenshot from 2014-12-19 10 08 04](https://cloud.githubusercontent.com/assets/4596845/5506454/5f40c4fc-8768-11e4-80d1-22dd5a069813.png)