Keywords are words or phrases that best describe the information you need for your topic. They are the most essential parts of the question!
Pick the most basic words that define your topic and will have an impact on your results.
Example:
What long-term effects are caused by chemical weapons?
chemical weapons AND long-term effects
Try the following techniques to specify your results even more!
Phrase Searches
If your chosen key term is one or more words, use quotation marks before the first word and after the last word. This will tell the system to search the key term as a phrase.
"chemical weapons"
This will ensure that your results include only those articles in which the words are adjacent to each other and eliminates any instances of the words appearing in different sections of the article, thus not relating to your topic.
Truncation
Shortening a keyword to its basic root and adding a special character (usually an asterisk, "*") at the end will tell the computer to search for all variations of the word.
Searching for weapon* will find:
weapon, weapons, weaponry, etc.
*Not all systems allow for this. Check the help screens to see if this can be done. This function is most commonly available in subscription databases.
Nested Searches
Nested searches tell the system what operation to complete first. Usually, the system will read your search from left to right. When you use a nested search, everything inside the parentheses is searched first.
("chemical weapons" OR "chemical warfare") AND "long-term effects"
With nested searches, you can combine different search techniques in one search.
There are three Boolean Operators, AND, OR, and NOT. Using these between your search terms, tells the system more specifically what information you are looking for.
Using AND lets the system know that you want to retrieve only results with all of the terms included.
The point at which all terms overlap is shaded in. This is your results area. Your results with this search should only return articles which include BOTH of the terms, chemical weapons and long-term effects.
Using OR allows you to search for synonymous terms. It tells the database or search engine that you would be happy with articles including one or both of the terms.
Notice that the entire diagram is shaded. Your results should include articles with either term, chemical weapons or chemical warfare, or both.
Using NOT eliminates terms from your search.
Notice that the shaded area is only covering the term, chemical. This search should eliminate articles including the term, nuclear.