This turns on the spell check option. With this option on, any search
which produces no results displays a list of alternate-spelling
queries, which will produce more results. If a query produces one
result, the Search Appliance suggests other words similar in spelling to
the words you entered. The suggestions are based on the actual walk
database, so unusual spellings or terminology used on your site are picked up by the spell-checker. The number of suggestions
varies, depending on the Suggest Time Limit and Number of
Suggestions options. The default is on.