Here you can provide one or more filename fragments that will be matched against the file name used in any attempted search (the mv_search_file or 'fi' attribute). You may separate multiple match strings with whitespace, and may include shell-style wildcards.
The default setting is 'userdb', which means that by default you cannot use Interchange-style searches on the userdb table. (Pure SQL searches still work with it, however.)
For example, consider this setting:
NoSearch userdb .* *.secret
In this case any search file with 'userdb' in its name, or beginning with a dot, or ending in '.secret', will not be searchable.