Creating a lookup in mscrm without having Relationship

crmForm.all.new_secondarycontactvalue.style.display='none';
customSecondaryLookup("new_secondarycontactname"); function customSecondaryLookup(displayFieldName)
{
var fld = crmForm.elements[displayFieldName];
var temp = fld.value;
if (temp.length == 0)
{
fld.insertAdjacentHTML("afterEnd","");
}
else
{
fld.insertAdjacentHTML("afterEnd","

" + crmForm.all.new_secondarycontactvalue.value +"

");
}

fld.parentNode.removeChild(fld);
fld = crmForm.elements[displayFieldName];
fld.value = temp;}
On save event:
var S_CONTACT_NAME = crmForm.all.new_secondarycontactname.parentElement.parentElement.firstChild.innerText; crmForm.all.new_secondarycontactvalue.value = S_CONTACT_NAME;