In a nutshell, Google works by identifying text within webpages that match your search terms. While, in practice, the Google search algorithm is extremely complex. All the factors that go into Google's Page Rank are a closely guarded secret, and the algorithm is updated up to 6 times a day, but some of the major factors that are considered when matching search results with your search include: how recently the content was updated, how many times your keywords appear on the page, how many other sites link to a page, how "user friendly" the page is (i.e. how fast it loads, how mobile friendly it is).
1. Limit your search to trusted domains, such as educational sites and government sites, by typing site:.edu or site:.gov into the search box along with your search terms
2. Put phrases in quotation marks to keep the words together (like "climate change") rather than having google search for the words independently of each other