Vim doesn't work properly with cyrillic symbols

I'm trying to learn vim by its built-in tutorial. It is in russian so all the symbols are cyrillic. The most interesting thing is that vim commands doesn't seem to work with them. For example, I'm trying开发者_运维技巧 dw in normal mode with russign symbols, it deletes sometimes 1, sometimes 2 symbols within the word. It doesn't delete the whole word. But it works fine with latin letters. What's the reason?

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Sergey, the best option is not to use cyrillic symbols in normal mode at all. Since we are using vim mainly for coding, I guess the only case where you can feel uncomfortable with it is editing comments.

This is the best option also because actually the answer to you question depends on vim version. Here it is a russian article on this issue. I can add a comment to this article - map/langmap solutions doesn't work properly (as for me). So in this I'm agree with the author.