Skip to Main Content

Primary Sources: Searching Online

This guide is an introduction to primary sources research.

Limits of Search Engines

When searching online, it may help to keep these tips in mind:

Content must be indexed before it can be found in a search.  Recently posted material can take days (or weeks, or months) to show up in a search.

Everything isn't online.  If it's not online, it won't be found by a search engine.

Database content can be difficult for search engines to find.  The more layers there are between the search engine and the content, the less likely the search engine is to index it.

Databases and Online Directories

National Union Catalog of Manuscript Collections
Hosted by Library of Congress.  This resource contains bibliographic records for manuscripts sumbitted to OCLC's WorldCat catalog.  Collections listed online but not formally cataloged by libraries will not be listed here.

WorldCat (OCLC database)
The world's largest bibliographic database, containing over a billion records for library collections in 170 countries.  See the "Searching WorldCat" tab for tips on searching this database.

Using Online Search Engines

Some libraries and archives have web sites where they list and describe their research collections.  The tips provided here should work for most internet search engines.


Place your search phrases in quotes in order to find that exact phrase on web sites.  Otherwise, the search engine may search for sites containing any word in your search terms.  Do not use any spaces between the quotes and the phrase you want to search for. 

Example: "William Giles Harding"

Including Terms

Placing a plus sign ( + ) in front of your search term will require the search engine to find that term somewhere on the page, rather than in keywords which may be hidden in the coding in the background of the page.  Do not use any spaces between the plus sign and the word you want to include. 

Example: +"William Giles Harding" +papers

Excluding Terms

If you do not want to see pages from popular web sites, such as Wikipedia or Amazon, you can use a minus sign ( - ) to exclude pages with these terms.  Do not use any spaces between the minus sign and the word you want to exclude. 

Example: -Amazon.