mahéyasäm—of the greatest SB 1.19.30
mahéyasäm—of the most powerful SB 4.5.5
mahéyasäm—among other great personalities SB 6.15.10
mahéyasäm—of the great souls (the mahätmäs, or devotees) SB 7.5.32
Can't find any compound Sanskrit words containing mahiyasam.