You get no results when you use the Format facet to filter down result sets to Newspaper or eNewspapers
The Newspaper and eNewspaper format facet is used to limit results to only newspaper title records, not the articles in the newspaper. For example, a search for "Washington" would bring up the "Washington Post", but not stories about the state of Washington. To get newspaper articles, filter with the "Articles" format facet instead.
See the full list of formats available in WorldCat Discovery