If I do this:
/tp @e[type=minecraft:zombie_horse,sort=random] @s
or this:
/tp @e[type=minecraft:zombie_horse,sort=arbitrary] @s
or this:
/tp @e[type=minecraft:zombie_horse,sort=furthest] @s
or this:
tp @e[type=minecraft:zombie_horse,sort=nearest] @s
That teleport all zombie_horses to me.
it sorts the results, but does not limit it to any amount of entities. (add limit=<number>)