Crystal Reports - Select Expert Record - Double checkbox filter: This is an example of using two different checkboxes as flags to include.

CrystalReports_DoubleCheckboxIncludes

(
     ({BAQReportParameter.Check02}=TRUE)
     OR
     ({BAQReportResult.ProdGrup.Description}<>"Raw Materials")
) and
(
     ({BAQReportParameter.Check01}=TRUE)
     OR
     (
          {BAQReportResult.Part.PartNum}<>""
          AND
          NOT(ISNULL({BAQReportResult.Part.PartNum}))
     )
)