Keys are case insensitive and may be specified in any order. Using more than one key implies the logical AND of the keys. Because of this, specifying too many keys may cause searches to fail. If you specify keys that match a large number of domains, Netfind will list some of the matching domains and ask you to form a more specific query. When Netfind runs, it displays a trace of the parallel search progress, lessalong with the results of the searches.
More complete documentation is also available in that package.