When a movie or programme has no subtitles in the stream, the app can search them on OpenSubtitles.com and show them over the video. You need premium and your own OpenSubtitles account (free registration on their site).
Settings > Extended settings > External services integration > OpenSubtitles and enter your
Login and Password. This screen is hidden in Simplified mode
(Settings > Extended settings > User experience level).Audio and subtitles and choose OpenSubtitles under Subtitles.OpenSubtitles is in Parameters of the player menu, with the older
interface styles (see The player menu). It appears when the programme
playing has a title in the EPG.The app searches by the title of the movie or programme, and by its year, season and episode, when known. Pick a result
from the list; each shows its release name and the number of downloads. If nothing fits, choose Search at the bottom
and type another title; when nothing is found at all, the app asks for a title right away.
In the media library player, Off under Subtitles in Audio and subtitles turns the found subtitles off.
The results are sorted by your preferred languages: first those in
Settings > Player > Media tracks > Track language (Subtitles), then in Track language (Audio), then the language of
the device. Without any, English is used.
Subtitles are found by the title (or the IMDb / TMDB id of the movie, when the app knows it), not by the video itself. Their timing may not match a different cut of the movie or a broadcast with ad breaks: try another result.