Queries :: Date Range With UNION ALL

I used UNION ALL to get results from two queries and I Succeeded.Now I want these results to be in a date range, so I want to enter the "starting date" then the "End Date" to have may results in specific date range.This is the original code out of UNION ALL which is working fine:

SELECT Count(Patient.PatientID) AS CountOfPatientID, Patient.CauseOfAmpLowerLt
FROM Patient
GROUP BY Patient.CauseOfAmpLowerLt
HAVING (((Patient.CauseOfAmpLowerLt) Not Like ""))
UNION ALL SELECT Count(Patient.[PatientID]) AS CountOfPatientID, Patient.[CauseOfAmpLowerRt]
FROM Patient
GROUP BY Patient.[CauseOfAmpLowerRt]
HAVING (((Patient.CauseOfAmpLowerRt) Not Like ""));

And this is what I tried:

SELECT Count(Patient.PatientID) AS CountOfPatientID, Patient.CauseOfAmpLowerLt
FROM Patient
GROUP BY Patient.CauseOfAmpLowerLt
HAVING (((Patient.CauseOfAmpLowerLt) Not Like ""))
UNION ALL SELECT Count(Patient.[PatientID]) AS CountOfPatientID, Patient.[CauseOfAmpLowerRt]
FROM Patient
GROUP BY Patient.[CauseOfAmpLowerRt]
HAVING (((Patient.CauseOfAmpLowerRt) Not Like "") AND (PatientService.[Date of Service]) BETWEEN [Start Date] AND [End Date]);