draw polyline which point from sub-entities,it is possible?

hello again,I continue learning....

(setq ins (vlax-ename->vla-object ( ssname sele cod))  
       nombre (vla-get-name ins) 
    )

    (setq bloque1 (vla-item
                   (vla-get-Blocks      
                (vla-get-Document ins)
                   )
                   nombre
                 )
    )
  
(setq s_ent1 (vla-item bloque1 1))  
(setq pt1 (vla-get-startpoint s_ent1 ))
(setq pt2 (vla-get-endpoint s_ent11 ))
(setq s_ent2 (vla-item bloque1 2))   
(setq pt3 (vla-get-startpoint s_ent2 ))
(setq pt4 (vla-get-endpoint s_ent2 ))
(command "_pline" pt1 pt2 pt3 pt4 "c")

 why dont draw de _pline?

thank¡¡¡¡¡