How to work with Nested hierarchies in Crystal reports

Dear Members,

i wanted to know how to work with hierarchies (especially when they are multiple) in Crsytal reports, below are the few details of Crystal report.

Source for Crystal report          : BW Bex Query

Crystal report-Bex connector    : MDX driver.

Crystal report version              : XI3.1

Let me make my query simple, for eg: in Bex query, while working with Hierarchies, we can do drill down/up from parent node to child node level, but in case of crystal reports i don't know which function to use to achieve the same.

Anybody if you are aware, please respond or at least if you have any document, link which will explain how to work with multiple hierarchies in crystal reports, please share.

Thank You.

Thanks,

Sreehari.