Are there philosophical essays dedicated towards discovery in humanity?
The first philosophical book that comes to mind with that topic is The Structure of Scientific Revolutions by Thomas Kuhn.
The branch of philosophy about the creation of knowledge is called epistemology. Most books about epistemology concentrate on philosophy of science. There are some non-negligible reasons for this, such as the fact that there are more explicit arguments in science and more clear successes.
Karl Popper looked at the creation of knowledge in general and explained the creation of both scientific and non-scientific knowledge. He explained that knowledge is created by noticing problems with current knowledge, proposing solutions to the problems, criticising the proposals until only one is left and is has no known criticisms, then looking for a new problem. Popper applied his theory to many topics, including science, political philosophy and music. See "Realism and the Aim of Science", "Objective Knowledge: An Evolutionary Approach", "The Open Society and its Enemies" and "Unended Quest" by Karl Popper.
David Deutsch has made some improvements to Popper's ideas, including integrating it with the theory of memes, see "The Beginning of Infinity".