After decompiling .NET program I see chinese signs as a variables etc? I use reflector, this is some kind of bug or source prevent ?
I assume that you do not have access to the source code, and you are attempting to reverse engineer someone else's software. That can be legal in some cases, but it can also be something that can get you sued.
If this is software that others do not want you to decompile then it is highly likely that it has been obfuscated. That means that at the very least all the meaningful names for types and variables will have been replaced by generated symbols, devoid of meaning. The appearance of Chinese characters may be intentional or a side-effect of the decompiler being used, but regardless, you can be sure the original names have been removed.
Most obfuscated code has other transformations applied, to make it difficult to follow the logic of the program, to obscure string or other literals and to trick known decompilers into making mistakes.
The bottom line is that if you're trying to decompile obfuscated source code you're in territory that is legally risky and technically challenging. The bar has been raised, and perhaps you should not try to cross it.