One can only apologise for the unhelpful comments of those who have little interest in helping the newfolk in our Industry.
First, current definitions are at
FAR 1.2
Second, current ASI marking requirements are specified in
FAR 23.1545
(For both references, the usual caveat applies - when talking specific Types, the relevant frozen rules relevant to the design need to be looked at).
In respect of your specific questions, presuming that the instrument has been marked correctly - there are aircraft out there with instruments swapped from other aircraft without the markings being corrected and, no doubt, those with just normally occuring errors.
why in some airspeed indicator of some airplane the beginning of white arc and green arc is the same and in some other airplane is not the same (why some times the Vso & Vs1 is the same and in some other airplane is not the same )
If the thrust of the question is
"why is Vs0 not the same as Vs1" then
(a) generally, the two values relate to stalls in two quite different configurations so it would be quite unusual to find that they ARE the same.
(b) .. unless, of course, we are talking about a simple small aeroplane without flaps, with fixed undercarriage, and for which MTOW = MLW .. for which the two stall speeds WOULD be the same.