If all else fails try
"Do you speak English?"
If this elicits little response then follow up with
"Do YOU speak ENGLISH"
Again, if confronted with a bemused look go further with

Try making signals with your hands whilst doing this, the appropriate signal being to extend your arm and pretend you have a glove puppet on the end of it which is talking.

Remember, the louder you speak and the more you gesticulate the more chance there is that you will communicate effectively.

The alternative is to take some time before visiting a country and try to learn a little of the local language, but thats just a whole lot of effort to go to in order to communicate with people who are obviously too lazy to learn English. Which of course everyone should do, not that you're a xenophobe or anything like that.