If you have been using only keywords separated by spaces in searching for information using Google Search, then you are only using the "and" operator in your searches. The "and" operator looks for web pages that contain all the words that you typed in the search bar of the Google Search page.
There are other search operators that you can use to narrow down or widen the scope of your search results. You don't have to memorize the operators and their functions; just know that there's a way to specify more exactly what information you're looking for.
The "or" operator specifies that either the word or phrase that precede or follows the operator should appear in the pages that should be included in the results. Enclose a phrase in double quotes to tell Google that the phrase should appear exactly as typed in the web page that you are looking for.
Use the minus sign immediately before a word or phrase to specify that this word or phrase should not appear in the web page you are interested in. Use the plus sign immediately before a word or phrase to tell Google that you are only interested in that particular word and not any other word that includes it or derives from it.
Use the tilde sign before a word to specify you would like to include web pages that contain the synonyms of this particular word. Include an asterisk between two words to tell Google that you're interested in the phrase that contains both the beginning and ending words with one or more words in between. You can also use the word filetype followed by a colon and then followed by the document extension to restrict the results to only certain document types like PDF or DOC.
You can also restrict the results to only documents that contain the keywords in specific locations in the document like for example in the URL, in the title or in the body of the document. Use allinurl, allintitle and allintext followed by a colon then followed by the keywords to tell Google that all keywords must appear in the URL, title or body of the document. To use the operator for a specific keyword only, use the word inurl, intitle or intext followed by a colon then followed by the keyword.
Do you know what the "I'm Feeling Lucky" button is for? Well, it you press that button instead of the Google Search button, you will be immediately brought to the first web page that Google found relevant to your search query.
To find out if Google has indexed your web page, type the word info followed by a colon then type the URL of the web page and press the enter key. To limit the search to a particular web site only, use the word site followed by a colon and then the URL of the site you're interested in.
Use the word link followed by a colon and the URL of a web site to find out the web pages that have links to this particular web site. And to find web sites that are related to particular web site, use the word related followed by a colon and then followed by the URL of the site you're interested in. You can also use the Search within results option to search only the results that have been generated in an earlier search.
Further to using the"and" operator which is implied when using keywords separated by spaces, I believe that using more keywords on the search query returns more exact documents than using fewer keywords for the search. Google had mentioned to use as fewer search keywords as possible on the search query but I take this to mean the fewest keyword that would return the desired information. I still think that on average, more specific documents will be returned by providing more keywords on the search query.
Now you know the different search operators that you can use in your search query to more specifically target the information you're looking for. Use them to narrow or widen the scope of your search results and specify more exactly the information you need.
Read my other article Google Search Engine Basics for Readers and Writers at: http://laptopwriting.blogspot.com/2009/12/basic-use-of-google-search-engine-for.html.