First, I need to figure out if "Sanctus Libera" is an existing known title. If not, perhaps it's a user's request to create a fictional sheet music. The user might need a guide on how to find sheet music for the Sanctus, or maybe they're interested in creating their own. They mentioned a "libera" which might relate to Latin terms or the name of a composer. Alternatively, "libera" could be a typo for "Libera me," which is part of the Mass for the Dead (Requiem) starting with "Libera me, Domine." But the user wrote "Libera," so maybe it's part of another piece.