How to Remove variable from the Selection screen

Hi,

in BI 7.0, I have created a workbook with Multiple tabs, with each tab having different workbooks in it. I have 8 variables that are coming up in the selection screen. I dont need one of the Variable to be displayed in the selection screen. I know that we can go to the query & uncheck the option variable as Mandatory to make it not display. But the problem is, that variable is not in any of the queries that i used to create workbooks, its in some other query. But its appearing in this selection screen. So, is there any option to make the variable not to appear in the selection screen?

Thanks for your time.

Regards,

Murali