"Preview" history, I am running lion and when I double click on the preview icon in the dock, it seems to be showing me the history and not the "minimized" images only

When I am running "Preview" of few images and minimized 1 of them, if I double tap the tracking pad, magix mouse etc..., the gesture should show me what is currently open, the upper part of the screen and what is minimized, in the lower part of the screen. Instead, I get a lot of images at the bottom part along with the minimized images, it seems like it is showing me the history files as well. Is there anything I can do to fix this? Can I erase the history of "Preview"?

Thank You