Can you check if those files have some embedded metadata – in particular a Title tag?
If you have Local Media Assets enabled for that library/agent and prioritized it over the regular agents, Plex will use the embedded title to match the video. From what I understand, Plex is currently only doing that for mp4-type containers (mp4, m4v…).
Once you’ve fixed this, you might be required to perform a Plex Dance to make Plex forget it already matched those files:
move the wrongly matched files outside the folder monitored by Plex
scan the library for updates
empty trash
clean bundles
apply whatever fixes are required to the file / folder names (or in your case the embedded metadata)
return the files to their target location
scan the library for updates (again)
As a side note… you might want to put those technical information about your file in brackets to avoid Plex from confusing them as part of what it’s supposed to match (e.g. Taxi Driver (1976) [Bluray-720p].mp4, Beetlejuice (1988) [Bluray-720p].mp4).