What version of Premiere Elements and what computer operating system?
Have you opened the Premiere Elements program that you are using or gone to the workspace's File Menu/, and then File Menu/Open Project
Same idea for Premiere Elements 11 through 14. The screenshot here is for 13/13.1.
Have you been giving your projects distinctive names so that you can spot the one you want? Naming also helps to eliminate projects getting written over.
Are you posting because you cannot find your saved closed project?
Please consider and then supply details. Any questions or need clarification on the above, please do not hesitate to ask.
By previous saved project, I met the slideshow in organizer not video editor.
The answers are in the details. What version of Premiere Elements/Elements Organizer?
But, the generalized answer is - if you saved the slideshow in its Slideshow Editor (Slideshow Builder) as a Slideshow Project, you can go to the Elements Organizer browser part, and double click the thumbnail for the Slideshow Project save.
If your only save for the slideshow is as a wmv file, that cannot be re-edited in the Slideshow Editor (even if it has a thumbnail in the Elements Organizer browser section.
You can tell the difference between thumbnail for Slideshow Project and thumbnail for wmv by placing mouse curse over top right of thumbnail to reveal either "Video" or "Slideshow Project".
Please consider and supply more details.