I found some kind of solution ...
i select all my clips (i have over 100 clips in my video line) , and then i go on - clip,video options, and scale to frame size... and then i got all my clips scaled to frame size..
i need to to that every time i load that project
and why that problem started?
i think because i imported my footage in HDV, but my project settings are dv 720X576 pal
its crazy to pick all clips one by one and scale it just to see what u are working on, it is a disaster
so this is nice solution for this problem.