Developing Search Terms
Main Concepts
When developing search terms, begin by identifying the main concepts in your research question by selecting nouns important to the meaning of your question. Leave out words that don’t help the search, such as adjectives, adverbs, prepositions and, usually, verbs.
Example: How are birds affected by wind turbines?
The main concepts are birds and wind turbines. Avoid terms like affect (except the noun) and effect as search terms, even when you’re looking for studies that report effects or effectiveness.
Example: What lesson plans are available for teaching fractions?
The main concepts are lesson plans and fractions. Stick to what’s necessary. For instance, don’t include: children—nothing in the research question suggests the lesson plans are for children; teaching—teaching isn’t necessary because lesson plans imply teaching; available—available is not necessary.
Sometimes your research question itself can seem complicated. Make sure you’ve stated the question as precisely as possible.
Related and Alternative Terms
For each main concept, list alternative terms, including synonyms and singular and plural forms of the words.
Sometimes synonyms, plurals, and singulars aren’t enough. So also consider associations with other words and concepts. For instance, it might help, when looking for information on the common cold, to include the term virus—because a type of virus causes the common cold.
Check to make sure that your terms are not too broad or too narrow for what you want. Figuring out what’s too broad or too narrow takes practice and may differ a bit with each search.
Use Quotation Marks for Phrases
Put quotation marks around any phrases among your terms so that the phrase is what’s searched for, rather than the separate words. “Common cold” instead of common cold is a good example. Without those quotation marks, just think how many sources Google or other search tools would waste their/your time on, things that have nothing to do with our sniffles.
and not the results for the individual words.
Use Wildcard and Truncation Symbols to Broaden
Consider whether using wild card or truncating symbols would help find variations of a word. For instance, the wildcard symbol in wom?n finds both woman and women, and the truncating symbol in mathematic* finds mathematics, mathematically, mathematician, etc.
Activity: Wildcards and Truncation
Consider AND, OR, NOT
You can often do more precise searching by combining search terms and by using the words AND, OR, and NOT. These are known as Boolean Operators. Generally, using these operators narrows your search, making it more precise.
subsets of sources.
AND – If the main idea contains two or more ideas, you’ll want to use AND to combine those terms in your search statement. To look for information about spiders as signs of climate change, you’ll want to have both terms in the search and perform an AND search. That’s what automatically happens in search engines such as Google and Bing unless you tell them to do something different by using OR or NOT
OR – If the main idea has several synonyms, use OR to combine them. Most search tools search for all terms (AND) by default, so you need to use the operator OR between terms to let them know you want to find any of the terms, not documents with all the terms.
NOT – If the main idea has a common use you want to exclude, use NOT to exclude that word. For example, if we were looking for information about illegal drug use, we would want to exclude prescription drugs from the search results. This is commonly done with NOT or the use of the minus (-) sign. In Google, to exclude a word use -word with no space between the – and the word you want to exclude. If you put a space in there, Google will not exclude the word. (When using some search tools, you have to use AND NOT before the word to exclude it.)
Using Parentheses with Multiple Operators
When a search requires multiple Boolean operators (AND, OR, NOT, or their symbols), you must use parentheses to group the appropriate terms and quotation marks with each Boolean operator. The resulting statements connect terms, remove terms, and organize search terms in ways that result in complex and precise searching.
The use of parentheses may remind you of the mathematical statements written in math courses. The reason parentheses are necessary in searching is that search tools, including Google, generally perform their operations from the left to right of a search statement. If you are using multiple Boolean operators, then the way to make sure that the search is done as a whole statement requires that you use parentheses to combine the sets in your statement.
Never use parentheses unless you are using multiple Boolean operators.
for complex searches.
Being skillful at this task of envisioning the effects Boolean operators have on a search can help you troubleshoot your own search statements when they aren’t turning up what you expected.
Example: “United States” AND (immigration or emigration)
Can you tell that the searcher wants to find information about the United States’ immigration or emigration?
The searcher will find more with this arrangement than would turn up if the statement had been “United States” immigration emigration. That’s because the latter arrangement without parentheses would find only information that was about both United States immigration and emigration, instead of either.
Example: (cats OR dogs) AND (treatment OR therapy)
Can you tell that the searcher wants to find information about either treatment or therapy for either cats or dogs?
That’s a different search from what the searcher would have gotten if this statement had been used: cats dogs treatment therapy. Anything found with the latter statement without parentheses would have had to be about both— not just either—therapy and treatment for both—not just either—cats and dogs. So the latter statement would have turned up fewer pieces of information.
