Hi Darrin,
You can use an advanced condition in your data selection, and write an expression that look for both Tax or Freight on the line.
Here's an example:
=(pos('Tax', @(¤t.line, 1, 200)) > 0) or (pos('Freight', @(¤t.line, 1, 200)) > 0)
This advanced condition will be true if either Tax or Freight is found on the line. Note that it reads characters from 1 to up to 200 on the line, but if your lines can have more than 200 characters, feel free to increase the 200. (or reduce it if your lines can't be more than a certain number of characters)
Hope that helps!
Regards,
Raphaël Lalonde-Lefebvre