Hard drive with my work crashed and burned. I deleted all of my raw files. Is there anyway that I can re-export my files which I can still see in LR
No. Your images have gone for good. (Why didn't you have backups on another drive!)
The thumbnails in LR are only small database previews- not your images.
There are programs that can extract images from the previews but they will only be of low quality.
Check out this site-