In general, information that has been been created, selected, or reviewed by experts is more reliable, helpful, and accurate. These "experts" are often referred to as "scholars" and thus the articles and books they produce are referred to as scholarly sources. Libraries purchase electronic databases such as EbscoHost and ProQuest which contain these articles. This is often how you, the student, obtain access to this scholarly information (at least in electronic format).
Scholarly articles are not typically free and accessible from Google searches.
Periodical databases index articles that originally appeared in print journals, magazines, and newspapers. Many but not all of the articles are also available electronically. The following databases cover a wide range of topics and will yield articles on most any subject.