Simply because there are no alternative out there allowing to do so. I tried manually on Spotify first but the search tool is optimized for popularity and relevance, not text matching. Which is almost impossible to find the exact text matching. Some database exist with text matching options (MLC or MusicBrainz) but it takes a lot of time to gather the relevant tracks (no preview and no direct comparison of tracks). That where the app Say it with a playlist is very good: type your text, select options, generate... And you've got a playlist with different versions of tracks to select.