$ pwd
/tmp/rajesh
$ cd fol1
$ ls -ltr
total 0
drwxr-xr-x 2 wmuser wmftp 256 May 11 17:28 sub
$ cd ../fol2
$ ls -ltr
total 0
drwxr-xr-x 2 wmuser wmftp 256 May 11 17:28 sub
$ cd ../fol3
$ ls -ltr
total 0
drwxr-xr-x 2 wmuser wmftp 256 May 11 17:29 sub
$ find /tmp/rajesh -type d -name "sub" -exec mkdir {}/subapp \;
mkdir: 0653-357 Cannot access directory {}.
{}: A file or directory in the path name does not exist.
mkdir: 0653-357 Cannot access directory {}.
{}: A file or directory in the path name does not exist.
mkdir: 0653-357 Cannot access directory {}.
{}: A file or directory in the path name does not exist.
$