[Evolution] What ui/*.xml file defines the search drop downs?

["Matthew A. R. Sherian" <mars mars-tmc hq themunicenter com>]

I have a drop down in my evolution install at work that has "Message Contains" as an item, I would like to have this option at home as well. Currently that doesn't exist and I am under the impression that that is defined in the UI XMLs.  If this is true which XML file is it in? I have been unable to locate it with a grep for the label of the drop down item.