Is it possible to retrive a file I deleted (by mistake) for more than 30 days?

There is no such option to retrieve them after 30 days. As the recycle bin also kept them for a period of 30 days

If you have a backup of your Mac and/or Time Machine backup, when the file was still on the Mac, you could retrieve it via a Restore.

There are third party data recovery apps/services, but in 30 days the deleted file could very well be overwritten by other data, and recovery will, most likely, not be possible.