The 50c stamp highlights the Four Geneva Conventions, which are:-
(a) The first Geneva Convention protects wounded and sick soldiers on land during war.
(b) The second Geneva Convention protects wounded, sick and shipwrecked military personnel at sea during war.
(c) The third Geneva Convention applies to prisoners of war.
(d) The fourth Geneva Convention affords protection to civilians, including in occupied territory.
The 60c stamp is aboutMedical-social relief.
The 65c stamp highlights the Principles of the Red Cross.
And, the 70c stamp is for the Red Cross which is for peace.