Well.. assuming you mean this:

%myhash = (
key1 => [abd, bcd, cde, def, efg],
key2 => [abd, def],
key3 => [efg, cde, tgh],
key6 => [cde, tgh, efg],
);
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You could loop through all the keys of %myhash, sort the value array and compare it to all other elements.

This would scale to n(n-1) which is roughly n² so it's very slow.