Search
What the search index holds, through the same query the dialog runs.
The search had three separate bugs — a filter fighting a filter, results that were heading fragments, table cells run together without separators — and all three were invisible, because nobody could see the sections the index is built from.
Reading it
One row per heading, not per page. That is what the index stores and what the dialog groups back into pages, so a page with eight headings is eight rows.
The indexed text column is exactly what FTS5 matches against. If a word is missing there, no query will find it, however correct the page looks.
FTS5 matches terms and prefixes, not substrings: caching finds caching, cach
finds it too, and aching finds nothing. A search that comes back empty is
usually this, not a missing page.