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CE/EEE 350: Introduction to Environmental and Ecological Engineering

This guide includes resources and information helpful to students taking CE/EEE 350.

Developing a Database Search Strategy

A search strategy is the combination of keywords and synonyms you choose and the way you connect them with AND, OR, and NOT.  These are also known as Boolen operators.  An example search strategy is at the end of this sheet.  Developing good search strategies helps increase the efficiency and effectiveness of your database searches.

To focus your search and ensure you are getting sources that combine all aspects of your topic, use AND.  Adding terms with AND will give you fewer results.  For example, you could search the terms car AND hydrogen AND environment, with will find sources that use all three of these terms.

A photo example combining search terms using AND.

To expand your search and find sources that use different words for the same thing, use OR.  Adding terms with OR will give you more results.  For example, you could do a search with the following phrase car OR vehicle or automobile, which will give you sources that use any of these terms, alone or in combination with each other.

A photo example of expanding your search using OR.

To omit certain terms from your results, use NOT.  For example. You may have done an initial search and found that many of the sources you found are related to Ford.  This is great, but you are interest in other car manufacturers too.  You want to filter out the articles about Ford so you can only see the ones about other manufacturers.  For example, a search for car NOT Ford will discard any of the articles that mention Ford.

A photo example of excluding terms using NOT.

Other search tips:

Many databases use an asterisk (*) to truncate words if you want to search for all words with that root.  For example, *environment would search for environment, environmental, environmentalism, ect…

Put quotes around a phrase that you want the database to search as a phrase, rather than as individual words.

Group synonyms inside parentheses using OR between each one.

Search strategy example: using the example keywords and synonyms below, one search strategy might be:

(car OR automobile OR vehicle) AND hydrogen AND environment*

Photo illustrating how to use all search methods in one search.

Database Search Help

Different databases may utilize distinct search functionalities and features. To maximize the effectiveness of your searches it is helpful to spend some time exploring the "Help" or "Support" information provided. For example, here is a screenshot of the help information available in Engineering Village.  Notice there is a great deal of information pertaining to the database's "Search" functionalities.

A photo example of the help page for Engineering Village database.