How to use Or condition in dashboard filter?

[agaikar-1658151]

1. How to provide Or condition between 2 dashboard filter. ------in order to resolved this I tried user custom filter $(table1.Filed1)=”Value1” or $(table2.Filed2)=”Value2” but here it become static.
2. in a dashboard basically there are 2 filters eg ARC Code= “A1234”, Point of Sales Code = “PS678, PS456” .It should basically show the data in table even if either of Data matching. 
3. and it should not be static, user should be able to select more ARC code and POS Code in Dashboard.
4. Can we put user define parameter in custom filter ?