How to create the URI for condition OR in Bugzilla using C#

Question

I have to make a search in bugzilla for different conditions, depends on what the user select. For example, i want to search in the same time, for bugs that have :

(STATUS_BUG = In Progress AND Version_Bug = 1) OR (STATUS_BUG = NEW AND Version_Bug = 0)

Version_Bug it's a custom field, added by me. I don't know how to create the url from code, for condition OR. I've tried to use the advance search filter, but the url it looks very ugly.

Thanks in advance, Andreea.