Click the little down arrow on the quick filter in order to access
it's menu and select Apply to Worksheets > All using this dataSource
Hope this helps!
I agree with Daniel, but there are 2 ways to fix this:
You can select "all using this work sheet" which is probably best for you. The image below shows you that step using Daniel's Method.
But you may also want to select just one worksheet. To do that, from the above window select the second option that says "Selected Worksheets" and then use this window to choose which worksheets you want to the filter to affect.
I tried both methods. Apply to all using this data source works, but it affects every sheet, and that's not what I want. When I apply to specific sheets, of course the underlying sheets are affected. This isn't a big deal if I don't publish everything to the server. I could also base the dashboard on a copy of the sheet. I'm a newbie to Tableau, working thru the interview process with them. Love what I've seen so far.
Yes, the underlying worksheets that make up a dashboard are always affected when filtering the dashboard they are a part of. Note that you can hide underlying worksheets by right-clicking on the sheet tab and selecting 'Hide Sheet.' This helps keeping the workbook manageable and simplifies the publishing process.
Great suggestion Daniel!