Database view with complex join

Hi everybody,

I need a help about next case:

I have a view ZLFA1 which lists vendors. Also, I have a view ZCONT which lists some documents for vendors.

Now I need to add ZCONT in ZLFA1 and connect them via LIFNR field, so ZLFA1 should list only vendors which exist in ZCONT. But since there are more than one record in ZCONT for particular vendor, I am getting more than one record in ZLFA1 for particular vendor and I should get only one.

In other words, I need a condition like:

WHERE ZLFA1-LIFNR EXISTS IN (SELECT DISTINCT LIFNR FROM ZCONT).....

Is it possible to do via transaction SE11, and if not, how can I do it?

Thank you in advance.