Search Statements

At this point in your search process, you are moving from merely identifying main concepts and similar search terms to developing more complicated search statements that can do more precise searching.

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.

Quotation marks around the phrase common cold.

Putting a phrase in quotes returns results containing that phrase, and not 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(s). For instance, the wildcard symbol in wom?n finds both woman and women, and the truncating symbol in mathematic* finds mathematics, mathematically, mathematician, etc.

Asterisks (*) match any number of characters that fit the rest of the pattern, and the question mark (?) matches a single character within a pattern.

Using wildcard characters allows you to find variations on a word.

ACTIVITY: Wildcards and Truncation

Open activity in a web browser.

Consider AND, OR, NOT

You can often do more precise searching by combining search terms 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.

Venn diagrams showing how searches using AND and NOT narrow search results, while those using OR expand search results.

The Boolean operators AND, OR, and NOT exclude or include subsets of sources.

AND – If the main idea contains 2 or more ideas, you’ll want to use AND to combine them. To look for information about spiders as signs of climate change you’ll want to have both terms in the search and are performing 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 term OR between terms to let it know you want to find any of the terms. In the previous example of Latino small business growth, we would want to also use the term Hispanic.

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. (When using some search tools, use AND NOT before the term.)

Using Parentheses with Multiple Operators

When a search requires the use of more than one Boolean operator, use parentheses to group the terms with each Boolean. Doing that usually involves putting parentheses, quotation marks, and Boolean operators (AND, OR, NOT or their symbols) in specific places in the search statement. (The operators or symbols used can vary from search tool to search tool, but the concepts are the same.)

The resulting arrangements connect terms, remove terms, and organize search terms in complex ways, much like you might write mathematical statements.

Parenthesis around two terms - (cat or dog) and (president and “white house") - to find references to cats or dogs owned by presidents in the white house.

Parenthesis are used with Boolean operators to combine terms for complex searches.

Being skillful at this task of envisioning the effects Boolean operators have on a search can help you troubleshoot your own arrangements 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 arrangement 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 arrangement had been used: cats dogs treatment therapy. Anything found with the later arrangement 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 arrangement would have turned up fewer pieces of information.

Activity: Search Analysis

Open activity in a web browser.

Practice with Search

Take some time to practice searching precisely – start by identifying main concepts, then listing related terms (with the help of wildcard and truncation symbols), and finally constructing search statement.

Activity: Search Practice

This example focused on the research question “How does a person’s diet affect the risk for getting cancer?” Work through the three activities below.

Search TermsOpen activity in a web browser.

TruncationOpen activity in a web browser.

Search StatementsOpen activity in a web browser.

Activity: More Search Practice

This example focuses on the research question “What is the effect of gamma radiation on crops?” Work through the three activities below.

More Search TermsOpen activity in a web browser.

More TruncationOpen activity in a web browser.

More Search StatementsOpen activity in a web browser.