Where can I find the purchase code and documentation of the theme?
You can find your purchase code on your profile's downloads page in download dropdown for our item.
For documentation, it is available in your download package that you got from ThemeForest. Furthermore, you can also see online document of each product in http://docs.knightheme.com/themename or offline documents for the product that is included and updated with the theme package
Example: Online docs for primary will be http://docs.knighthemes.com/primary