Functions don't work when drilling down from a dimensional model

[jilin]

Hi Everybody

I have a problem with dimensional model. Is there anybody can help, thanks in advance.

I wrote a expression likes filter([Product line], [Gross margin] > .30. I want get filtered product lines. After I enabled the drill up/ down function in the RS, I ran the report and drill down to the second level, it should be product type, this filter didn't work as upper level.
Similarly, ordinal function doesn't work as the below steps. It always return 1 no matter which level you are.
How can I apply such functions in the each level when drilling down/up with a dimensional model? thanks.