I've read the 80:20 principle and it makes his sense how we should focus 80% of our time on the little things that matters and things that would give us great success. The more we focus on little productive things, the more our chances on success instead of focusing out energies on a lot of random things without clear objectives and productivity.

The second one I live do much is Think and grow rich, it teaches the fundamental principles that harnesses the power of our mind, bringing things we desire into life.