NodeJS send string

As I see Node JS can't send string to client.
When I use socket.write("string") client doesn't receive anything. socket.write(new Buffer("string")) — same situation.

var b = new Buffer(15);
b.write("string");
socket.write(b);

It looks like something works, but client receives string along with a lot of blank space.

var b = new Buffer(6); //6 - lenght of string in bytes
b.write("string");
socket.write(b);

Again nothing!

var b = new Buffer(7);
b.write("string");
socket.write(b);

Now there's less blank characters.
My head really hurts. Is it really complicated to send simple string?
Waiting for my savior :)