If I understand your requirement correctly, you can filter this directly with the Date field:
1. Put Date on the filters shelf.
2. I assume here you want to filter by Month/Year (since you are showing your chart by month), or you could choose Individual Dates. But for now, choose Month/Year and Next >
3. In the Filter Dialog box, choose "All", then go to the "Condition" tab. These three tabs on top work sequentially. First, you choose to look at ALL dates, then on the Condition tab, we'll apply a condition. You could select specific months on the General tab if you wanted, then the condition would apply to only those selected.
4. In the "Condition" tab, choose "By formula:", and type in SUM([Sales]) > 0. Then click OK.
5. And the result is this. only months where Sales numbers are found are displayed.
I noticed you had another filter in the view, you can add that as well if you want, and months where both filters are true will be returned.
Sample data test_v10.4.twbx 20.8 KB