Top-level domains tell you what type of institution the information comes from:
© Photo by Tumiso, pixabay license
Before using the information found, you have to assess its quality and relevancy:
Accuracy
Authority
Objectivity
Currency
Coverage
Be aware that Google use algorithms (PageRank) to filter, or tailor, the search results, based on previous searches you have done – the sites you have viewed, what you clicked on and other data that can be gathered from your browser. So the exact same search, using exactly the same search words, can return different results for different individuals.
Get further:
Pariser, Eli. "Beware online filter bubbles." Filmed February 2011 in Stockholm, Sweden. TED video, 8:47.
https://www.ted.com/talks/eli_pariser_beware_online_filter_bubbles