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Using Google: advanced

The advanced search facilities in search engines allow you to submit more complex searches and so search more effectively. By utilising these facilities you can eliminate some irrelevant hits and so reduce the number of results to a more manageable number.

Boolean Operators

One of the key features of an advanced search is the use of Boolean operators to combine the words or phrases that you are searching for. Google makes its advanced search easy by the use of boxes explaining the type of search that you can carry out. For example:

The Google advanced seach screen

  • 'with all of the words' is the equivalent of the Boolean AND operator
  • 'with the exact phrase' is the same as using quotation marks
  • 'with at least one of the words' is the equivalent of the Boolean OR operator
  • 'without the words' is the equivalent of the Boolean AND NOT operator

You are not limited to using the above advanced search interface. You can use the Boolean operators yourself to construct a search string which you enter into the simple search box. The operators must always be entered in upper case or they will be ignored altogether in the search. For example:

  • Using the AND operator: children AND poverty AND africa
  • Using phrase searching and the OR operator: "red indian" OR "native american"
  • Using phrase searching and the AND NOT operator (in Google this is represented by the minus sign): "special education" -hyperactivity

For further explanation of Boolean operators and help to combine keywords effectively yourself, look at the constructing a search string section of this tutorial.

Limiting your search

In addition to constructing an effective search string you can use Google's advanced search features to limit your search. For example:

The Google advanced search screen limiting options

  • Language: You can use the language drop down box to limit your search to pages written in one of over thirty different languages.
  • File Format: This is a specific feature of Google which allows you to search the web for specific type of files, eg Portable Document File (.pdf), Word (.doc) or Excel (.xls). This can be useful as some reports and guides are only available in PDF format and not in plain HTML.
  • Date: You can limit by when the page was last updated. This enables you to limit your search to the most recent pages or a certain period of interest, therefore reducing the number of results returned.
  • Occurances: Google will look for your keywords anywhere in a web page. This option allows you to specify that the keywords appear only in the URL, title, or the text of the page. Limiting a search to page titles can be a poweful tool for focusing your search.
  • Domain: This limits the search by the information that is found in the URL (Uniform Resource Locator) or Internet address. For example, if you wanted to limit a search to a specific country add the country code into Google's domain box (eg. .uk for uk; .hk for Hong Kong, .no for Norway). Many of these country domains are easy to guess, although a list of all the country codes  is available.
    You can also limit your search to a particular type of institution, for example, .ac.uk for academic institutions in the UK. Other organisational domains include .edu for US educational organisations, .nhs.uk for the UK National Health Service, .gov.uk for UK Government, .gov for US Government.

Try it yourself

Use the Google Advanced Search to practice constructing a search string and effectively limiting your searches. For example, you could search for web pages that have the exact phrase native American children in the title of the page, written in the English language, which have been updated in the past year and come from the domain .edu (US educational organisations). This is a very precise search and will only return a small number of results.

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