This is related to the way you define the pathway in the .bashrc file.
(1) Make sure to create only STDB directory.
(2) Make sure also the tmp directory is created if you wanna save your project there.
(3) Ctrl + h ====> to unhide files in home directory.
(4) gedit the file ===> .bashrc
(5) Add instruction inside the .bashrc file.
STDB=/user/home/STDB
export STDB
(6) Assume that the STDB directory resides in the home directory. If it is inside synopsys directory, then just add synopsys name after the home directory such as below.