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Find Articles: Search: Keywords & Boolean Logic

Find subject-appropriate databases, learn how to search effectively within databases, and access the full text of articles.

2. Search: Keywords & Boolean Logic

These strategies can be applied to most research databases, as many have similar interfaces and features. However, you may need to adapt your search somewhat depending on the database you are using. 

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Getting started with database searching

The first step in developing a search strategy is to determine what concepts you are looking for, then brainstorm keywords that express those concepts. Keywords can be combined using Boolean logic [definition].  

Keywords

Begin by brainstorming some keywords related to your topic. For example, if your topic is:

The impact of television advertising on children

...then your most important concepts are: 

televisionadvertising & children

Image of concepts: television, advertising, and children

Advanced Search

Once you have selected a database, look for an Advanced Search option. The Advanced Search will give you more control over your search. 

You may also see an option to Add rows.

Multiple rows for searching:

Image of multiple search box rows

Boolean operators: AND

Databases use Boolean logic [definition] to interpret search queries. Keywords are organized into sets. 

Use AND when you want the database to search for articles that include all of the terms in a set. 

For example:

children AND television AND advertising

...retrieves articles that use all three terms, but ignores articles that use only one or two of the terms. 

Using AND narrows your search. 

Searching with AND:

Image of a search with several search rows

Arrow pointing downwards

Veen diagram showing how the terms children, television, and advertising will overlap when combined with the word AND

Similar terms

Different authors will use different terms to express the same concept.

For example, one author may say "television" and another might simply say "TV." Yet another could use the broader term "media." 

Brainstorm synonyms or related terms:

Image of similar words: television, tv, and media. Children, and youth

Boolean operators: OR

Use OR when you want the database to search for articles that include at least one term from a set. 

For example:

television OR TV OR media

...retrieves articles that you use any of the three terms. 

Using OR broadens the search. 

Searching with OR:

Image of search bar displaying a search for television OR tv OR media

 Arrow pointing downwards

Image of a veen diagram highlighting where television, tv, and media will be used interchangeably

Boolean operators: NOT

Use NOT when you want the database to exclude any articles that use a specific term. 

For example, perhaps you are finding too many articles about the effects of violent TV shows on children, and you want to eliminate those results. With this search:

(children AND television) NOT violence

...the database ignores all articles that use the word violence. 

Searching with NOT:

Image of search box rows with AND connector

Arrow pointing downwards

Veen diagram highlighting how the term violence will not be searched for if you use this connector before the term violence

Phrases

If you are searching for a phrase, put it in quotation marks. For example:

"product placement"

... will only retrieve articles that use the two words together. Articles that use 'product' and 'placement' separately will be ignored. 

Truncation & Wildcards

Truncation symbols and wildcards allow you search easily for the singular and plural versions of a word, different word endings, and alternate spellings. 

The asterisk (*) is a common truncation symbol, but some databases use others, like the number sign ($). For example:

child*     ...retrieves children or childhood, etc.  

student*     ...retrieves student or students, etc. 

You can also put a wildcard symbol in the middle of a word. For example:

adverti*ing

...retrieves advertising and advertizing.

Searching with phrases, truncation & wildcards:

Image of search bars with a complex search and search terms and connectors in each box

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NEXT Next button 3. Search: Narrow and Broaden

Definitions

Boolean Logic: Also known as Boolean algebra, Boolean logic is a mathematical system developed in the 1847 by George Boole. It is widely used in the design of digital circuits for computers, and in computer science generally. In Boolean logic, search terms are organized into sets and combined with operators such as AND, NOT and OR. 

More on Boolean logic: