In future you may want to consider storing them in jewel cases if the data is important to you. And use better media.
Is it hot or humid where the discs are stored?
If you or a friend has a LiteOn or Samsung drive, try reading the discs in one of those. They’re your best chance of getting the data back off those discs.
I had some Ritek G05 discs, notorious for their deterioration, and I was able to recover the data and back it up to Verbatim discs, with an older LiteOn drive.