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Course & Subject Guides

Writing in the Biological Sciences - Oakland Campus

This guide is designed primarily for students who are relatively new to reading, writing for, and finding literature in the biological sciences.

Searching Techniques

Article databases, online library catalogs, and many popular search engines share several general searching techniques. Once you master these common searching techniques, you will save yourself time and find more relevant results.

Selecting Keywords

The search terms or keywords you use to search are what determine the results you get. Here's a good exercise to help you generate keywords:

1. Express your topic in a topic sentence:  "What is the effect of water pollution on freshwater amphibian populations?"

2. Generate keyword search terms by identifying the main ideas or concepts within the topic sentence: "What is the effect of water pollution on freshwater amphibian populations?"  --> effect, pollution, freshwater, amphibian

3. Expand your search terms by brainstorming related terms or synonyms that describe your main ideas:

  • Effect; impact
  • Pollution; pesticide, acidity, pH, heavy metals
  • Freshwater; river, stream, lake, pond
  • Amphibian; frog, salamander

Combining Search Terms

You can create complex search strategies by combining keywords using the linking words AND, OR and NOT. For example, if your search terms are biodiversity and wetlands:

  • AND - Narrows and focuses the search results. The search biodiversity and wetlands finds only results containing both the terms biodiversity and wetlands.
  • OR - Broadens the search results. Searching biodiversity or wetlands will find results containing the term biodiversity or the term wetlands or both terms in the same result.
  • NOT - Excludes any result containing the term listed after the not.  The search biodiversity not wetlands will find results containing the term biodiversity but not containing the term wetlands. Use not cautiously since it excludes all mentions of the term in every context.

Field Searching

In some databases you can restrict searching your terms to specific sections or fields in a database record, for example the article title or author name.

You can tailor your search by combining information from different parts of the record, like combining an author name with a subject term, or focus your search by restricting terms to an article title or abstract.

This is frequently done by using a pull-down menu to select the appropriate field for each search term.


Searching the root of a word without specifying a particular ending is one way to find variations on a word that relate to the same core concept without searching each word separately.

Some databases automatically search terms for singular, plural, and various other endings.

Some databases use a truncation symbol to indicate that any ending is acceptable after exactly matching the letters entered.

  • gene*       will find     gene, genes, genetic, genetics, genetically                                             but not      genome or genomics
  • vaccin*    will find    vaccine, vaccines, vaccinate, vaccinated, vaccination, vaccinations

The actual symbol used will vary among databases. The asterisk (*) is most common, but some use a ? or other symbol, so check your database.

Phrase Searching

Searching for exact phrases instead of individual words can focus your search so that more results are directly relevant to your topic. Different databases and search engines accomplish this in different ways. Two common ones are:

  • Quotation marks - Some databases treat words enclosed within quotation marks as phrases. Searching "Atlantic coastal wetlands" will find only results containing those three words next to each other in that order.
  • Default setting - In some databases, words typed next to each other are automatically searched as an exact phrase. Searching Atlantic coastal wetlands will only find results containing that exact phrase

Remember: Exact phrase searches can focus your results, but they can also miss some relevant results. Searching the phrase "Atlantic coastal wetlands" will not find wetlands of the Atlantic coast or coastal wetlands of North Carolina, both of which are relevant.