maybe because I didn' t install it in the defuat loaction?

Exactly. 1. Set the environment variable PDK_ROOT to the path to the pdk 2. Provide xschemrc do not use the one you are currently using

I have also just figured that out. I forgot to set the enverionment variable. thank you.

set PDK_ROOT this way:

export PDK_ROOT=....../share/pdk

the path you givve to PDK_ROOT must be the open_pdks installation on your system. Then in the same terminal (and in the directory where you copied the oprn_pdks xschemrc template file ) run xschem