"Hm?" Hermione looked up, surprise etched into her expression. "It's an idea finding spell, usually using keywords. You just wave your wand in an elliptical motion over the book or books, like this," she demonstrated, moving her wand in a lateral oval encompassing all of the books, "and say "Scoh-poh-ray-shee-oh'. You see?" The books inched away from one another and flipped to the first match. "When you're done with that passage, tap the book and it will move to the next mention. Here, you try."