To create a Report that will show all Sales generated from Customers within a specific Category, customize a built-in report:
1. Navigate to Reports>Sales>Sales by Customer
2. Click Customize on the bottom left
3. Specify a Name for the report
4. Click Edit Columns
5. On the Add Fields section:
a. Click the Customer/Project folder
b. Click Customer Category and click Name
6. Click Filters
7. On the Add Fields section, click the Customer/Project folder then click Customer Category
8. On the Choose Filters section, under the Value column:
a. Filter: equal to
b. Click the Icon on to select multiple categories
c. Add all the Categories then click Done
9. Click Save
The report can then be accessed from: Reports>Saved Reports