I checked out Selling Olga because I really enjoyed the author's first book, Hearing Birds Fly: A Nomadic Year in Mongolia. Selling Olga was also well-written, but not as good as Hearing Birds Fly. I ended up skimming parts of the book because they seemed repetitive and the prose wasn't quite worth reading for its own sake.
As the other reviewer noted, the book concentrates in large part on the conduct of the governments and organizations ostensibly trying to keep peace and stop trafficking. This was interesting, but the coverage doesn't really venture beyond the journalistic. That is, I was hoping to understand how people could treat each other like commodities. Are being enslaved by your neighbor or you yourself turning into a parasitic bully things just below the surface in all people? But there is never any of this sort of psychological or sociological exploration. That's okay, it just made the book a little less interesting to the general reader, I think. It ended up being a timely and topical expose rather than something more enduring about the human condition.
As for the subject matter, it is distressing to think this is going on. Why isn't there more focus on it in the cable news world? Probably because the narrative here of UN and EU involvement doesn't fit the progressivist narrative.