> and I put it on my time line, then apply a filter to the clip on the timeline.
> the filter is automaticly applied to the whole clip in the browser?
It wouldn't do that. What you're probably did is that you put In and Out points, put the clip into the timeline, then put a filter on the clip in the Viewer. But you never opened the copy of the clip from the timeline, so the Viewer still has your master clip in it, which was opened from the Browser.
First cut the clip into the timeline, then double-click on that clip *in* the timeline to open just that one copy of the clip.