Huge difference between "docs" and "indexed"

(from github.com/pcolmer)

Is it normal for there to be such a massive difference between the number of docs (2,744,050 in the screenshot) and the number of indexed files (11,532)?

(from github.com/marevol)
Select “special” checkbox.

(from github.com/pcolmer)
Thank you for this suggestion.

Can you please explain where I can find this checkbox, and what it does? I’ve searched the documentation and cannot find a mention of it, and I cannot find the checkbox in the web UI.

(from github.com/crpgbogor)
You need to tick the special button marked with asteriks (*), just above the fess.suggest crawler on your screenshot. I also experience this, I don’t know if this is normal or not. Currently testing it manually. See also https://github.com/codelibs/fess/issues/673