Are you sure there isn't a typo in the "Available" word, as it is in the document? Or, is it in a page named like the one where "available" is, because page names are compared case-insensitive and only one hit is returned.
Speaking of searching, it not clear to me what happens if I turn on
Lucene. Does this replace searching back-end for regular search box, or
I have to add new page for searching?
No, it does not replace normal search. You will have to write a search page that uses Lucene. Maybe we should have this page in the Code area on
xwiki.org.