Recommendations and Adjustments To improve search results, admins can recommend documents they think are most likely to be useful for specific searches. Google calls this "KeyMatch" and provides a place to type or import a list of queries, URLs and names for the recommendations. Similarly, the synonym list shows a suggested alternate term, such as "physician" when a user types in "doctor", or the preferred "handheld computer" for "PDA". These are clickable query links, and can be combined with KeyMatch links.
Nice article. Personally - I do not think any intervention is taking place on the public engine. One of the advantages of an engine that is for the same set of pages - by the same group of people - is that keywords and stuff can be used. That is basically what is happening here.