File shredders overwrite file data before deleting the file. On an SSD, there is a chance that the file data is still somewhere on the SSD due to how SSDs re-map the logical address space to physical space for write-leveling but you'd need software to rip the underlying raw storage data and likely have to manually reassemble the files as the exact block ordering information has likely been lost even if the data itself survived.
On a regular modern HDD, physically overwritten data is pretty much unrecoverable through conventional means, you'll need to scan platters using a magnetic force microscope and reconstruct the data from there using forensic analysis if enough residual magnetic field from previous writes is still strong enough...