The window contains the name of each group which contained at least one matching article. When you open such a group, you see a list of all the articles which matched your search criteria. You can also use the Search News command when a subject list or article window is active. When a subject list window is active, the command searches the group for that subject window. When an article window is active, the command searches all the groups in the Newsgroups header line of the article.
All searches are case and diacritical insensitive substring searches.
To turn this on, edit the News Server settings for the server you are searching on. If your server does not support the XPAT command, you won't get any search results. In that case, you should turn XPAT back off. Depending on the XPAT setting, searching news on the server like this can take some time, because MT-NewsWatcher might have to fetch all the headers for the groups being searched to look for the articles that match. Searching in Articles that You have Read Often, you may find that you remember reading some interesting tidbit in an article some time ago, and you want to go back to it, but can't remember which article it came from.