" + " Searches
Google ignores common words and characters such as "where" and "how", as well as certain single digits and single letters, because they tend to slow down your search without improving the results. Google will indicate if a common word has been excluded by displaying details on the results page below the search box.

If a common word is essential to getting the results you want, you can include it by putting a "+" sign in front of it. (Be sure to include a space before the "+" sign.)

Another method for doing this is conducting a phrase search, which simply means putting quotation marks around 2 or more words. Common words in a phrase search (e.g., "where are you") are included in the search.

For example, to search for Star Wars, Episode I, use: Star Wars Episode +I

" - " Searches
Sometimes what you're searching for has more than one meaning; "bass" can refer to fishing or music. You can exclude a word from your search by putting a minus sign ("-") immediately in front of the term you want to avoid. (Be sure to include a space before the minus sign.)

For example, to find web pages about bass that do not contain the word "music", type: bass -music

" ~" Searches
You may want to search not only for a particular keyword, but also for its synonyms. Indicate a search for both by placing the tilde sign ("~") immediately in front of the keyword.

For example, to search for food facts as well as nutrition and cooking information, use: ~food ~facts

Phrase Searches
Search for complete phrases by enclosing them in quotation marks. Words enclosed in double quotes ("like this") will appear together in all results exactly as you have entered them. Phrase searches are especially useful when searching for famous sayings or proper names.

"OR" Searches
Google supports the logical "OR" operator. To retrieve pages that include either word A or word B, use an uppercase OR between terms.

For example, to search for a vacation in either London or Paris, just type: vacation london OR paris