Laravel not save the error files in storage folder

For example, if I get a laravel error in my view generates a file with string numbers:

ErrorException in 19d7345bcbbf651c1b34743d90b6a81a950dbcec.php line 3:

Previously these files are stored in the storage folder, but it is not currently saving.

how can I activate the saved again?

with a environment variable?

via Chebli Mohamed