A large database where you can search by the exact filename: OpenSubtitles.org.

A lossless file downloaded directly from a streaming service. H2... (likely H264): The video compression codec used.

Based on the true story of Loretta McLaughlin, the reporter who first connected the Boston Strangler murders. 📝 Subtitle Information

If you are looking for the text (subtitles) for this specific release, you can find them on major subtitle repositories. The "MULTi" tag in your filename suggests the file may already contain several built-in subtitle tracks.