For your knowledge in your PBOK to be valuable you need to constantly refine it.
Refine by adding clarity to what is written.
Refine by creating links to related knowledge.
Refine by adding hashtags according to a taxonomy.
Refine my refining the taxonomy used to tag the knowledge.
Refine by combining the knowledge into topics.
Refine by creating indexes and links into the knowledge.
There is no way of creating all of this interconnectedness at the beginning, it needs to be an ongoing practice.