A compound clause combines any number of simple clauses, using the same logical operator: AND or OR. (The NOT operator is not supported.) You can combine both simple and compound clauses.
The query builder automatically creates placeholders for simple clauses, but you must explicitly insert a compound-clause placeholder yourself. To do so, select the query title or an existing AND or OR statement, and click one of the or AND Group/OR Group buttons. Then, specify the field name, comparison operator, and value for the clause using the Click here to add link under the compound-clause placeholder.