There's a similar problem with my native language[1] and "sorry". The standard word, samaavenna literally means "forgive me". As a former British Colony (Sri Lanka) most of us have got used to the English words -- even non-English speakers will automatically say "sorry" or "thank you".
But once "thank you" is said, most people awkwardly respond with "ah", because there's no phrase in the language for "you're welcome".
Come to think of it, we don't even have a universal second person (a "you"). You need to know the social standing of the person before you can address him/her!