General Search Features
Most of the major search engines support the following search techniques, although each search engine operates a little differently. To find out which features are supported by a search engine, read the HELP file. There is usually a link to a HELP file near the search box or near the top of the search engine's home page. If it is not in one of these places, try selecting the search engine's Advanced Search option. Often this page will have a HELP file if the basic search screen does not.
Just like other Internet resources, search engines often change their appearance and features with little or no notice.
Bottom Line: If you are not certain which techniques the search engine uses or if your search statement does not work, reread the HELP file.
Some search engines are case sensitive, requiring that proper names and place names be capitalized. In general, when a search statement is entered in all lower case, both lower case and upper case will be retrieved. The reverse is not true. When upper case is used, the search engine will only retrieve the exact match. For example, AIDS will not retrieve the common word, aids.
Most search engines support Boolean searching, allowing AND, OR, and NOT searches. Some search engines require that the Boolean operator be capitalized; others do not, although those not requiring capitalization accept it. Therefore, it is a good idea to capitalize any Boolean operator.
Many search engines use a simplified form of Boolean operator, replacing the operator with a symbol:
- the + sign for an AND search
Example: +drinking +driving searches for the words drinking AND driving, in no specific order in the text of the web page.
- the - sign for a NOT search
Example: +dolphins -football will search for documents which contain the word dolphins but NOT the word football
Google defaults to an AND search (automatically placing an AND between terms), and uses a - sign to indicate NOT. This means that you do not have to type AND in your Google search statements. However, for explanatory purposes, in this course the AND operator will be included in search examples, and for class exercises you should include this operator in your search statements where applicable.
Search statements combining more than one type of Boolean operator must also use parentheses around synonymous terms. This technique is called nesting. The parentheses tell the search engine to perform that search first. For example, suicide AND (teen OR youth OR adolescent) will search for documents containing any or all of the terms within the parentheses before combining that result with the word suicide.
Phrase Searching and Truncation
Most search engines support the use of quotation marks around words, terms or names you want searched as a phrase, i.e., appearing in exactly the order you enter them. For example, "ozone layer depletion" searches for this exact phrase with the words in the order given.
When devising a phrase search, be sure to evaluate the likelihood of your phrase being used by others. For instance, if you were doing a search on the benefits of reading to children, "reading children" would not return results as well as "reading to children." Phrase searching is the one time you may use minor words like of, in, to, etc.
Some search engines automatically look for singular and plural forms of terms as well as -ing or -ed endings. Others use the asterisk (*) to specify that all endings of the root term be searched. As was discussed in Lesson Two, this technique is called truncation.
Some search engines allow you to limit your search to specified fields, such as the title of the document, a word from the URL, the domain name, the type of file, and the availability of such features as images, sound, and video. In the following table, four types of field searching are demonstrated (title, URL, domain, and file type) in addition to phrase searching and truncation. All of these syntaxes will work in Google except for the truncation symbol (Google now uses stemming technology to automatically truncate for you).
|Goal||Common Syntax||Example Searches||Syntax for Examples|
|To limit search to an exact phrase (i.e. words together in order)
||You're looking for the phrase health care reform.
||"health care reform"
|To find plurals or variations of a root word (truncation)
||You want to find any of the following terms: clones, cloned, cloning, etc.
|To specify that your search term should be found in the title of the Web page
||You're looking for sites that have tomb raider in their Web page titles.
|To specify that your search term should be found in the URL of the Web page, including paths and subdirectories
||You're looking for sites that have NASA in their urls.
|To limit your results to a particular domain or site
||1) you only want educational sites (i.e. the domain is .edu).
2) you only want to search within the Library of Congress's website (http://www.loc.gov).
|To limit results to a particular type of document (i.e., Word document, Excel spreadsheet, PDF, etc.)
||you only want Microsoft Word documents
The next table demonstrates how these techniques can be combined to create effective search statements.
|Search Query||Search Techniques||Search Statement|
|You want government sites that discuss bioterrorism
|A friend told you about a great site on elephants that had wildlife in the URL and Africa in the Web page title
||URL searching, title searching
||elephants inurl:wildlife intitle:africa
|You need an Excel document with statistics on international adoption
||Boolean operator, phrase searching, file type searching
||statistics AND "international adoption" filetype:xls
|You are looking for sites that relate to children who have ADHD
||nesting, Boolean operators, phrase searching, truncation
||(ADHD OR "attention deficit hyperactivity disorder") AND child*
These are just a select sample of search techniques commonly available for search engines. For additional search features, read the HELP file of the search engine you are using.