Index not used

Why is the index on the node “Titre” not used in the following query?

When I use the explain function on the query I get the answer: This query will retrieve all documents from the doctype DJO_BDJ_STOCK/Texte.

I attached the schema to my message. See the enclosed document.

declare namespace tf=“
for $r in (code de la s
Legi_Texte.tsd (20.6 KB)

Why does it say the contains clause say $r/text() instead of just $r?  I think it should just be $r