It is called a type of Upaya Kosalla. (according to Abhidhamma and Commentaries)Have you ever heard of the problem solving skill? It's a very useful in life but you can't learn it from any definite source.
It is called a type of Sutamaya Panna. (according to Abhidhamma and Commentaries)Can you learn investing from a guru or book or course or university degree
It is called a type of Cintamaya Panna. (according to Abhidhamma and Commentaries)Who taught the people who invented the touch screen or microprocessor or petrol engines? Who taught the first rich person to be rich from trade? Did they went to school? Who taught the guy who built the first aircraft or tank? Who taught the guy who built the first aircraft carrier or submarine?