Openstaad - functions not in reference book

Hi all

I have off late been extensively using openstaad For creating n analysing my structures.  I wonder there are many functions which are being used by people but has no documentation.  Openstaad reference alone doesn't not have all the functions. Kindly suggest ways or documents from where commands can be Learned.

Wind or seismic load is not defined clearly inopenstaad reference

Regds