Can DAX Filter support dynamics filter expression

Hi experts,

I try to dynamics filter table results and show as another table.

Basically, i would like to create a new table "FT" using filter function, filter on table 'Original' with a dynamics filter expression on what i selected for able mySelection

FT = filter('Original','Original'[key] = SELECTEDVALUE(mySelection[Key])) 

But, it seems the PowerBI does not show the expected results.

If i change the filter expression to static one --- 'Original'[key] = "static selection", it works

Any idea?

How could i achieve such dynamic filtering?

Thanks

Rake