Trying to remember a movie... help?

In my Spanish class in High School, we watched a movie that was in Spanish. I have absolutely no memory of what it's called, but if you can help me discover it, I would be very thankful!

It was a very dark drama, about a brother and sister (or perhaps a girlfriend and boyfriend) who wanted to go to America. In particular, they were intrigued by the idea of going to the bathroom inside the house, and flushing it away. Toilets seemed like a totally cool thing. I think it was supposed to be in the 70's or 80's, but it could have been a bit earlier or later.

Anyway, they are trying to go through many countries to get up to America, and experience a lot of hardship along the way. In particular, I remember a scene that involves a large arena, like a football (soccer) stadium, though I can't remember what happens. There are a lot of people killed, so it's very likely rated R or PG-13. It's in Spanish and was only subtitled in English.

The woman (maybe the man, too) ends up in America in this awful apartment with a disgusting toilet.

If you have any idea of what this movie might be, let me know! It's one of those things that has been bugging me for years. I remember how that movie made me feel, more than the details of the movie itself, and would like to watch it again. Thank you, Y!A