Moved to Photoshop Lightroom forum.
Click on the catalog panel on the left, click on All Photographs, then turn off all filters (ctrl-L once or twice)
Search for the photo by the file name, using the search bar (press backslash, then click on text, then from the dropdown menu select file name, and then enter the file name in the text field)
I'll give it a try. I've been using Lightroom for years but somehow I lost some pic. that were in there. thanks. Pat