perk books are broken.

If you only do quests then you are going to only open containers in random POIs that may have no connection to the types of magazines you want. Pick and choose the right POIs to scavenge in without a quest and you'll start finding more of what you want.

At the end of the day, the magazines are random. You get a boost in what you've perked into but not a guarantee. But you can push chance more your way by looting the right types of POIs and quests don't always take you to the right types of POIs