To take advantage of the potential of Google's Search engine, it's important to know some of its basic tricks

• Keywords: Quality of the responses depends on the quality of the words chosen. For example, "computer" does not give the same results as "PC".
• Typing words in lowercase give you every opportunity not to miss any important reference.
• Quotation marks (" ") make sure that the search engine takes into account all the words.
• Signs "+" and "-" add constraints to your search.
  For example, you can search for documents on George Lucas who only speak of Star Wars (george lucas + star wars) or on the contrary who do not speak of the film (george lucas star wars)
• Wildcards: Google accepts the use of a wildcard (*) for the location of a missing word in a phrase.
• The tilde (~) allows Google to display not only a word but also its synonyms, in a broad sense, that is to say, beyond the true grammatical synonyms, related terms.

More searching options:

• "site: xxxxxxxxxxxxxxx". Returned results will be only from the selected site.
• "author: xxxxx xxxxxx". Identifies latest articles published by the author in question.
• "insubject: xxxxx" Results show the articles on related requested subjet.
• "location: xxxxx" Displays information bearing to the specified eyes.
• "source: xxxxxx" Results extracted from any source.
• "allintitle: xxxxxx" Results show the articles where all searched keywords are available in the title

The search bar includes also a calculator. Type the calculation directly in your search bar and press enter to have the result displayed.

More about Google seach engine: Google Help