More than fifty years after the first edition of Thompson's seminal Motif-Indexof Folk Literature, we present an online search engine tailored to fully disclose the index digitally. This search engine, called MOMFER, greatly enhances the searchability of the Motif-Index and provides exciting new ways to explore the collection. This is enabled by our use of modern techniques from both natural language processing and information retrieval. The key feature of the search tool is the way in which it allows users to search the Motif-Index for semantic concepts, such as ‘mythical animals’, ‘mortality’, or ‘emotions’. This paper will explain the motivations for creating the search tool, explicate the production process, and show in a number of case studies how the search tool can be used to explore the index in innovative ways.