“For now, neither scheme is practically useful: Preprocessing currently helps at the extremes, when the database size balloons toward infinity.”
Wei-Kai Lin, Ethan Mook and Daniel Wichs built single-server private information retrieval with preprocessing, and won Best Paper at STOC. Wichs spent years trying to prove it impossible. The result is real and the headline is not. Private search works once your database is infinitely large.