I was born in Russian and went to school there in middle 90ies. During my school time we had a special subject called "TRIZ" that stands (in Russian) for "theory of inventive problems solving". Apart from its technical bias as basically a method to optimize workflows in industry, our teachers also provided many different examples how using the principles of TRIZ can help answer even normal, daily questions in an inventive way (if questions have these answers).
Many websites in Russian devoted to self-development and improvement of personal productivity contain large sections dedicated to this method. There are also just sites who only teach TRIZ as a method for solving non-technical tasks from daily life. According to the above-linked Wikipedia article this method is known at least to some top engineers and designers, but I have never seen or heard any application of it for personal development outside of the former Soviet Union.
Wikipedia article lists some related methods, but none I would know. Maybe there is something I am missing here? In Russia (during my time and in my home district) almost every school used to teach it...