An old movie poster used a quote "in space, no one can hear you scream! " why this is true or not true?

Yes it is true. Because "Sound does not Travel in Space" Because In empty space, there is no air, and what we call "sound" is actually vibrations in the air 

And also IF sounds really does travel in space, The Comets, The Stars,The Black holes, And the Supernova's would create unimaginable sounds that could somehow make our EAR DRUMS burst. 

A Supernova releases as much energy as the Sun emits in it's entire life or 1044 joules 
which is about ten octillion megatons of TNT (~1028 joules) 
So you'd need about 10 trillon (~1013) of the most powerful hydrogen bombs to equal a supernova. SO if SOUND TRAVELS IN SPACE, ITS LIKE AN EVERYDAY WARFARE (Depending on how many supernova's have occured on the universe)and we need to use a STRONG soundproof device to protect our ear. XD 

Hope this helps. XD

The masses of the objects and their densities