Mushi was able to read and understand the scroll he had been handed, probably thanks to both the Knowledge Talent and his INT Score as he looked it over, this knowledge on the scroll somehow just making sense to him. It was a bit strange. The Scroll was for the Fire Cantrip Spell 'Flame Hands', which ejected a cone of fire. He figured he could either wield the Scroll as one would wield a Tome, only it would just be for casting the Spell on it, or if he poured over and took about ten minutes or so he could learn the Spell on the Scroll which he could use with his wand, although the process would probably destroy the scroll in the process. 

Sumato was able to figure out the same thing. The Spell on the scroll she took was one that could be used with her Tome. It was an Arcane Cantrip Spell 'Magic Shield', which was a basic Arcane Cantrip for creating a defensive barrier in front of them for basic protection. As how Mushi figured out, she could either wield the scroll like a Tome or spend about ten minutes and learn the Spell through close examination and reading of the scroll.