I have written a lot about learning objective thinking at http://pikakoulu.blogspot.fi but it is in Finnish. There is a basic course in objective thinking, of which you can find an English translation at http://quickerlearning.blogspot.fi , and then there are, mostly in Finnish but something in English too, advices in developing in intelligence with the help of other areas of life.
There are also advices abour developing in intelligence in my old video channel http://www.youtube.com/khtervola on playlists Increasing intelligence and Rationality of feelings there.
About work efficiency in engineering type of work, but also on other types of work, see the book on a link from the first blog post at http://workandfreetime.blogspot.fi .
If one wonders what typically Finnish there is in my thinking skills, maybe the advices about choosing good strategies in life would be an important part of that http://finnishskills.blogspot.fi/2015/11/healthy-ways-of-living.html .