I'm stuck and confused how to go about defining user groups in bugzilla. Here are my requirements.

For a product PDT_A, have two sets of users - the core product group PDT_GRP and the rest of the company OTHERS. PDT_GRP should have exclusive bug creation and modification rights on PDT_A, while OTHERS should be able to ONLY search and view the bugs logged.

I've been able to create PDT_GRP (entry/mandatory/mandatory/canedit) but haven't got a clue how to create the OTHERS group

How do I go about creating these groups?