Make your purpose to pick out the significant points that you don't already know. This was my problem from the beginning. I read to get new information so I have to make multiple passes with different purposes. The first purpose would be "I'm reading [XYZ] for the purpose of finding the main points" or whatever and then the second would be "What is new here that I don't know yet? What have I never seen before that MAY be what I'm looking for?" Trust me when I tell you this works.
Here's proof. I've affirmed this purpose so much that when I did the dictionary game I envisioned a word that wasn't even in there- "TREE" isn't in that dictionary. I'm so used to looking for what I don't already know that I'm noticing things the authors left out themselves. Even though that wasn't my specific purpose "to find words that should be there but aren't" I'm so used to looking for what I don't already know that maybe I'm immediately drawn to loopholes in the books themselves. Now that may not sound significant to you but I think it's an example of spillover- where what you do in one book helps you in others. Why I envisioned "tree" only to find it not in there is beyond me.
In reading Psychological or Spiritual books I use the additional purpose of "What do I already know but AM NOT DOING?" And sure enough I quickly find exactly that. Then I go on to "What do I NOT know but NEED?" Maybe this is called Mind Probing what I'm doing here but you can state them as purposes (statements) in the beginning and then later as questions.
