Well i do disagreed with the other comment posted. Piedras is much much better them Magnolia or any of the other films that were mentioned.
specially about non real characters, i think that someone just wrote that only because he never lived in the Spanish society like i did (and i'm not Spanish), is a very real film with real characters, very well done by one of the best Spanish actress Antonia San Juan.
about be a European film in contrast with an American film, well we different societies, personally i dislike American modern films a lot (i like the classics and some of the Andy American films but they are very few).
Is a film about the continuous Constitution of a person, liked or not we all make mistakes but some can learn about the mistakes.