You see the rule editor when creating a new rule or editing an existing rule.
The rule editor let you:
On the first line of the criteria editor you can select how to handle multiple matching criteria.
Each subsequent line is a criteria evaluating a caracteristic of the file. If you need more than one criteria, click on the “+” button on the right at the position above which you want to insert it at.
You can reorder criteria using drag and drop.
Tip: You can insert additional compound criteria by holding the option key while clicking on the “+” button (which will change to “…”).