Use other sources as well. Like lectures and other books. They help open the mind.
Also avoid regular reading. If all you feel you can recall was from dipping you would have to regular read again. That would take about 30 to 45 minutes of traditional reading 10 pages of a textbook and you have to do it at least twice. So you you would spend an hour to 90 minutes with one chapter. That's normal for textbook material ideally you'd want to rapid read it last and that would take about 15 minutes for the traditional reader. You want detail but this method is too slow, right?
Use PhotoReading and use repetition.
Go through the chapter superreading first, find one or two answers spend something like less than 6 minutes with a 10 page chapter, Then skitter 2 or 3 times. 7 minutes each layer for that chapter. Assuming you did one superread and 3 skitters you spent 31 minutes with the chapter and eyeballed them 5 times already. Compared to the 75minutes to 2 hours that you spend with traditional reading to eyeball the pages 3 times. you spent 31 minutes with the PhotoReading system.You still have the option of a rapid read.
If you're not getting recall after 5 activation layers of 10 pages it means you are still passive in your approach. Your purpose isn't clear so your questions are weak. Know your purpose know what you aim to learn form the text and how you can apply what you learn and your questions are much more valuable.
Alex