从控制器传递查询对象，通过Laravel中的Ajax（）进行查看

Question

When I click the option, function ajax_lead() is called

    <select name="project" id="project" onchange="ajax_lead()">
              <option selected="" >KSL</option>
              <option>M101</option>
              <option>Berjaya</option>
    </select>

The ajax_lead() in app.js

function ajax_lead(){
          var project = $("#project").val();   
          console.log(project); //get the project name successfully

          $.ajax({
                url: "/project_lead?project="+project,
                type: 'get',
                success:function(response){   
                }
              }) 
    }

Controller

 public function show_lead2(Request $request)
    {
        $project_selected = $request->input('project');
        //get the project passed from ajax

        $lead = new Lead;
        $lead_by_project = $lead->lead_by_project($project_selected);
        return view('SAM.Lead.lead_index',compact('lead_by_project'));
    }

Model (return the $lead to the controller above)

public function lead_by_project($project){
        $lead = Lead::join('pams_phase','pams_leads_noname.phase_id','pams_phase.phase_id')
        ->join('pams_project','pams_project.project_id','pams_phase.project_id')
        ->join('pams_users','pams_users.id','pams_leads_noname.assign_id')
        ->where('pams_project.project_name',$project)
        ->select('pams_leads_noname.created_at','pams_project.project_name','pams_leads_noname.name','pams_leads_noname.phone','pams_leads_noname.email','pams_leads_noname.location','pams_users.display_name')
        ->paginate('6');

        return $lead;
    }

However, it fail when I want to pass the $lead_by_project to the view that I set in my controller. Error in console :

app.js:12639 GET http://sale.test/project_lead?project=KSL 500 (Internal Server Error