An Official Website of the United States Government
There are several categories such as “By Agency”, “By Year”, “By State” etc. Select a checkbox within a category to refine your search results.
Each of your selections is listed in the “Narrow Search Filters” bar. You can uncheck these selections to remove them.
When you select multiple values within a category, the results will include values that match either of the selections. For example, selecting “2005” and “2007” in the “By Year” category will display results that include either 2005 OR 2007 in the results.
You can refine your search results across categories. To narrow down your results, select multiple values across different categories. The results will only include values that match the selections across the categories. For example, selecting “2005” in the “By Year” category and “NASA” in the “By Agency” category will only display the results that contain both “2005” AND “NASA” in the results.