however, when i tried to do same command bt only blink 1 LED at receiver (pin 13), by using 2 arduinos+xbees as tx and rx, it didnt blink at all.
If you remove the wire, and replace it with a wireless link, and it (whatever it is) no longer works, how can that be a coding issue?
It looks to me like you have not configured your XBees correctly. You haven't even mentioned what kind they are, or how (or even if) you have configured them.