Subtitles are added in netflix if you select them.
Hi, I am located in the netherlands, and have someone who is fluent in thai.
I added the thai subtitles in the netflix profile settings, and now, after 2 weeks i magically see the thai subtitles appearing on many series and movies that were released to many countries.
Af first they did not appear, and a help request at netflix onl resulted in "licensing" bla bla but it really seems netflix neede some time to update it possibilities.
unogs search does not know this, so maybe the profile you use to index your search should look for more and more languages?