Perhaps you should try some spelling variations:
"hernandez herrero, sergio," » "hernandez herrera, sergio," (Expand Search), "hernandez guerrero, sergio," (Expand Search), "fernandez ferrero, sergio," (Expand Search)
"fernando herrero, sergio," » "fernandez ferrero, sergio," (Expand Search), "fernando bermejo, sergio," (Expand Search), "fernando bermeo, sergio," (Expand Search)