Equal rectifier capacitor
What difference is there between the circuits? Which one is better?
  Can i made equal the capacitor with the capacitors in series?


Theoretically and simplistically both are as good as each other but you might find that the practicality of "one capacitor" makes it "better" whereas the likelihood of 6 parallel caps performing better on ripple current and ESR (effective series resistance) is to be considered favourably for the 6-cap solution.

To get 6000 uF with 6 series caps requires 6x 36,000 uF caps and the advantage is that you can use a lower voltage rating but only if you use bleed resistor to equalize the standing dc voltages across each cap.