What do you think about studying abroad? Is it good idea as Czech study a university in a foreign country? And which country is the best for such studying?:)

I am of the opinion that you have to weight up the pros and cons and think about what you expect from that. Pros can be the way to get responsibility, develop your verbal skills, meet new friends. Cons can be the amount of money you have to sacrifice, time, even friends.
I maintain you can learn a language here, in the Czech republic, as good as in another country. Speaking of my own experience, I have met a couple of people that studied at abroad and I wouldn't say their speaking, English generally was better.

Nonetheless, if you do not have to deal with issue of not having enough money and time then give it a shot. It can give you a lot.

You're right. Whole the thing has many cons. All the same, I would like go abroad someday. Not study, just stay any time there. But it hasn't been possible yet.

And something to the second point: the best place for such studying. Well, it is again up to you. I think almost every country can give you a lot, some can take you a lot too.
Even, let's say, India could be a great choice. Splendid culture, interesting people, gripping customs and stuff.
But mainly, I think, it depends on the knowledge of the country's language. So for most of us it would be English, in some cases German. All in all, it's up to your preferences, passions, interests. There are a load of options to choose from. Just some money and you can hit the road.