Solution 1:
Try:
find . ! -perm -g+r
Solution 2:
If you want to find files that are non-readable by you, you could use
find . ! -readable
Using `find -perm` to find when a permission is not set
Solution 1:
Try:
find . ! -perm -g+r
Solution 2:
If you want to find files that are non-readable by you, you could use
find . ! -readable