A search for video games (not in quotation marks) found 307,228 results.
Whereas, a search for "video games" (the set of two words in quotation marks) found 18,737 results.
Besides putting AND between search terms, another way to reduce the number of search results is to use phrases. If some words almost always occur in a specific order, you may consider them a phrase to search for. Put " " (quotation marks) around those words to find that phrase.
"united states"
"trojan war"
"apple juice"