The config snippet above looks like it has the default value(?), if that is indeed the case it shouldn't be necessary to have that explicitly in the config file.

IIRC the "Search Keyword" checks whether the "Referer" (sic) header from the original request matches that pattern at all and if it does, whether the "query" group from the match contains the text specified in the visitor group criterion.

Is it possible that you are just testing with a session that did not start with a request of the "right type"?

The config snippet is indeed the default value.  I have added it to the config just in case it was required. 

The test I am running is on the live deplyment via a google search.  The google search term is returning the page I am interested in and when I click on the link, the request is going to google and then doing a redirect to the live site.  This is how I would expect it to work.  I am just trying to wour out how to simulate this within the development environment.

We have now resolved this issue.  The problem was not caused by the setup of the visitor group, or by the configuration, it was how I was testing it.

It turns out that the initial referrer url is stored within the session state, thus you will always get a negative result.  When you test this you need to use a new instance of the browser and go directly into google and run the search.  This route will mean that visitor group will work, as a new session will be created.