The "bueno" in the expression "más bueno" applies rather to kindness, and not to quality, for which "mejor" is the only correct word (i. e., when you compare two models of car, the eficiency of two people at work, etc.). So, if you have to say that X is better person than Y (in terms of "X is more of a good guy than Y"), you have to say "X es más bueno que Y". Literally, "más bueno" means "gooder" (or even "goodest"). Hope it helped.

you can follow the explanations of the man/woman above but i must tell you that these expressions are considered to be extremely vulgar. You hear them on street...try to imagine which kind of people. if you allow me to suggest, you choose some other book. This book is from the hard times of franco dictatorship and unless one is 50 years old like me, it would be surprising here to find someone who even has heard about the book or film. Yes, they made a film in the 50's or so. Really, dont lose your time!

"Más bueno", sí existe. Es una expresión que tiene un uso costumbrista. Es un termino para comparar dos cosas, personas, situaciones. Significa que estre dos cosas una está mejor que otra.

"Más bueno" is not equal to "el mejor". Más bueno = mejor El más bueno = el mejor A es mejor que B = A is better than B A es el mejor = A is the best No se suele decir "más bueno". "Marcelino, pan y vino" es un libro para niños. "Más bueno" is not often used. Another similar example: "más malo" = peor