lost data: help?

[goldfish42]

A week or so ago I apparently made changes to a document instead of using "save as" like I usually do. Two documents, actually. My resume and my cover letter. I often tweak both a bit before sending them in, to shift the focus to the specific needs of the job I'm applying for. I now find I've lost the best standard cover letter and resume for planning jobs, the one I had refined over and over again until I thought it was as good as it could get. The changes I made were for a job that was mostly clerical, in a planning office. Not good. Now I have another planning job to apply for, and my "good" resume is gone.

Is there any way to recover an earlier version of a document?