In a humorous sense, some men may utter about the mysteries of understanding women, but this just takes it to a whole new level.
There's a book for sale that's titled "Everything Men Know About Women" that seeks to inform men about understanding women. One catch: it's filled with completely blank pages.
For sale on Amazon, it's available in paperback and in digital form on the Kindle. Published in 1995, it maintains a rating of 4.5 stars out of 5 on Amazon, and seems to have generated quite a stir with mainly positive reviews.
Obviously, the book is intended as a gag gift and not as a literal source of information. The book is popular with people who want to raise an eyebrow from their partner or friend.