Symbolism, Imagery, Allegory
Some of the names in Sold have some pretty important meanings. The thing is, though, that they almost all work as a sort of trick: the opposite of what a name suggests might be true about a character turns out to be true instead time and again. For instance Lakshmi is named after a goddess that brings light and prosperity to all—but when Lakshmi goes on a journey to work as a maid in the city, prosperity is nowhere to be found. And as we see this happen repeatedly with names, we can see that names in this book symbolize failed expectations.
Not convinced? Consider this: Habib, in Hindi, means beloved or friend. But for our purposes, this particular name is used ironically because Habib is the first man who rapes Lakshmi—and that's as far from beloved and friend as you can get.
Now get thee to Google to discover the meanings behind the rest of the names in the books.