The history of science is a rich discipline. There are many books on the subject. It sounds to me like you could do with a general overview to start with, to better orient yourself to the questions you are interested in. I use McClellan and Dorn's Science and Technology in World History: An Introduction when I teach my survey course to undergraduates, but there are other such books as well. What you may find attractive about it is that it takes a very broad definition of "science" and goes back about as far we can to the various types of knowledge we might call "scientific" in different world cultures. It also provides a nice survey of Western scientific thinking from the Greeks through the present day.