Perhaps you should try some spelling variations:
"rodriguez cabrera, gregorio," » "rodriguez camarena, gregorio," (Expand Search), "rodriguez carmen, gregorio," (Expand Search), "rodriguez arana, gregorio," (Expand Search)
"rodriguez calero, gregorio," » "rodriguez cabrero, gregorio," (Expand Search), "rodriguez alberto, gregorio," (Expand Search), "rodriguez pinero, gregorio," (Expand Search)