When searching for sources, everything depends on choosing the applicable search terms.
It is important to pick out key concepts in project descriptions, and use those as search terms; for example, What is the correlation between anorexia and depression? The key concepts here are correlation, anorexia, and depression.
One must also think outside the box and find synonyms, narrower terms, and/or broader terms, whether it be in English or other languages. Using the example above on the correlation between anorexia and depression then:
- ... a broader term could be ...
o anorexia → eating disorders
o depression → mental disorders
- ... synonyms / related terms could be ...
o correlation → interconnection, correspondence
o depression → melancholia
The following web sites can be useful in finding synonyms and related terms:
- Snara.is – various dictionaries (English and other languages)
- The various databases also offer thesauruses to aid in finding good search terms
Most often it is not enough to use one single search term; this usually returns limited search results. When using more than one search term, so-called Boolean operators, AND, OR, and NOT, are used and these are always written in capital letters.
- AND = to find two or more words together on a web page or in an article - for example:
o children AND behavior
o Iceland AND banks AND crisis
- OR = to find either word; good for searching for synonyms - for example:
o lystarstol OR anorexia
o fylgni OR correlation
- NOT = to exclude words which do not belong in the search results - for example:
o jaguar NOT car (when searching for sources on the feline Jaguar)
o fuji NOT film (when searching for sources on Mount Fuji in Japan)
Most search engines and databases understand space between words in such a way that both search terms should be searched for (or all the search terms if there are more than two search terms), although this is by no means universal.
In Google and Google Scholar the plus sign (+) is used instead of AND and the minus sign / dash (-) instead of NOT.
In most databases and library systems, the advanced search feature provides users with the option of selecting the Boolean operators AND, OR, and NOT in drop-down menus and thus connect search terms.
Place quotation marks “...” around search terms that are to be kept together, for example,
- “behavioral disorders”
- “business management”
- “body mass index”
Quotation marks can also be used together with Boolean operators - for example:
- Iceland AND “financial crisis”
- children AND “body mass index” NOT “United States”
- children OR teenagers OR adolescents AND “body mass index” NOT “United States”