This search engine will give links to newsletters that contain a search item and provide a bit of the text (see example below). Click on the link to open a newsletter in Adobe Acrobat (or other PDF reader); then use the Acrobat search tool to find pages within the issue that contain the search item.
Example: Initial Listings for "Hemlock Ravine"
(It's a screencapture, so links in this image are not functional;
a search for Hemlock Ravine brings up a total of 64 items.)