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Core biomedical index; includes MEDLINE and links to molecular biology databases.
Identify your concepts When searching for a topic, first it's best to break it up into keywords according to the main concepts.
For example, if you're interested in whether local farmers might see flax as a viable crop, your keywords might be:
Generate more keywords Next, you should think about other keywords that might also describe your topic. This helps make sure you don't miss relevant articles.
For example: flaxseed is sometimes known as linseed, crop might be a related term for farm, and Massachusetts might be expanded to New England and still be relevant.
Combine keywords to narrow or expand
Next, you can use the drop-downs with AND, OR, and NOT to tell the database to include or exclude various terms.
Flax AND farm will only retrieve articles with both terms, which creates a narrower search:
Flax OR linseed will retrieve articles with either term, or both (together with farm OR crop), which creates a broader search:
Find additional subject terms
Finally, you can look at the Subjects that are included in relevant records to discover terms that you hadn't thought about including.