Fixed filter to select multiple selections

[g23]

Hi all,

I set a filter to a fixed value so that when I open the app I see my data filtered by it as showing in the following picture:

The problem is that I need to be able to select multiple values for the same filter and not just one value at the time. Can someone give me any advice on how I can achieve this? 

Thanks

[Channa]

try passing multiple values into variable

vVariable=chr(39)&'ASHGHAL'&chr(39)&','&chr(39)&'RAIL'&chr(39)

build filter based on variable