by Bruno Sampaio.
I tried that but it didn't solve my problem.
Yes that's the path to my file with the relevant strings for my theme and I think there isn't any problem with the name "empty-applications" because some themes that come with Moodle also use a slash between words.
My code worked before when I was using a normal GET request, but now that I'm using ajax request the get_string always returns a empty value :s I already checked if there was any way to load the String API or something like that but I didn't find anything...
Thank you anyway!