"I do have a law section, and several books devoted just to inheritance law," Padma said. "It's a pretty important issue in Wizarding society, and can get complicated very quickly."
As for the others... Padma frowned, trying to think back over what she'd purchased for the store, and took a sip of tea.
"I know I have books on magical theory, the nature of magic, and other, similar books. I can't think of any that deal specifically with a person's soul, though I'm sure there must be a few books that address it. We can look at the section on magical theory, and if they don't have what you need, I can try to track something down to order it."
Of course... "I may need to check my back room," Padma said. "That's where I keep rare or dangerous texts. It may be that a book regarding magic's affect on the soul is technically labeled 'dangerous' by the Ministry. If it is, I'm required to keep it out of public areas, and the Ministry needs a record of who purchased those books."
Padma hid a smile in her teacup. "Of course, it doesn't mean you can't just read it at the table in the back room. As long as you don't purchase it, I don't have to report it. And personally, I've never been a fan of restricting knowledge."