Merge the queries:
  1. Select Query.
  2. Click Merge Queries.
  3. Enter the first query in the Primary Query field.
  4. Enter the second query in the Secondary Query field.
  5. Select Merge Operator=OR.
  6. Click OK.
  7. Repeat steps 2-6 until all queries are combined,
OR

Combine the queries using the Segment tab in Mail:
  1. Select Mail>Labels.
  2. On the General tab, mark the Create Output query checkbox.
  3. Select the Segment tab.
  4. Enter each query to be combined in the Input query checkbox.
  5. Unmark the Automatically overwrite existing queries checkbox.
  6. Click Print or Preview to run the Labels.
  7. When prompted, save the Output query.