OSB Search module

I create 3 categories, with 3 service into every categories, But when I choose a category into OSB search module form, it allow me to choose all service of all categories. Why? How I can filter service chosing until a categoriy?

I have the same problem!

Hi,
The OSB Search module only has feature to show options of (Venues, Categories, Employees .etc) through dropdown. It doesn't have feature to filter options through selected value. But your idea is good, i will consider to find solution to modify OSB Search module in near future.
Thanks
Dam