Search not working in Admin

I just noticed that I cannot do a search on one of my tables in the admin. I deleted the search setup criteria and re-entered the basic keyword query and a category dropdown match and it still does not return any results. It simply resets when I click search.

I doesn't appear that the data is corrupt since it all works fine on the front end. Also, this seems to be the only table that is malfunctioning.

The only thing I have done recently is to update from 2.16 to 2.17. Everything went fine, but noticed the search problem yesterday when I went to isolate a category and got no results.

Any ideas?