Forms :: Dynamically Passing Where Condition

I am working on 6i reports.I have below scenario to achieve.

I have FIND window and MAIN Window.

FIND Window: contains EMPNO, ENAME,and FIND button.

MAIN WINDOW: EMPNO, ENAME, SAL, JOB

If i enter something in FIND window, by clicking FIND button, it will populate data in MAIN window.I have below query in WHEN BUTTON PRESSED TRIGGER.

declare
cursor c1 is select empno, ename, job, sal from emp
where empno=nvl(:FIND.empno,empno)
and ename=nvl(:FIND.ename,ename)

begin
--here i am populating data into MAIN window block
end;

It's working fine.

REQUIREMENT: i want to pass where statement dynamically. Let us say if i pass only empno in FIND window, i want to pass 'WHERE empno=:FIND.empno' to existing select statement [I will keep select statement same without where condition]

If i pass empno and ename both, i want to pass 'WHERE empno=:FIND.empno and ename=:FIND.ename.

How to pass where condition to existing select statement based on parameters we pass in FIND window.