In general, you can't focus a fuzzy picture using editing software. Once it comes out of the camera fuzzy, there's not much you can do to eliminate the fuzziness. It would be better to avoid taking fuzzy pictures.
PSE does have sharpening tools, and there are some PSE add-ons and stand-alone programs which might help a bit. You might upload your picture to this forum so readers can offer suggestions. Click the camera icon to upload.