Finding and Winning your Perfect Mate was a publication by Dr. Jennings Rain, an expert in humanoid interpersonal relationships. Odo had the book in his quarters, and was discovered with it by Major Kira Nerys in 2373 when she was helping him reorganize.
Odo noted that he only read it because he thought he might be a solid the rest of his life, during his brief period of being humanoid. According to Odo, he had only read the first three chapters. (DS9: "In Purgatory's Shadow")