Why is only available to apply one psalm-doctrine to each item? For example weapon or armor can have 6 slots at max. But when i try to apply two different psalm-doctrines  (3 Psalm-codes required for each) it showed just one. Bug or intended?

It would be nice to apply more than one doctrine for item, maybe with some tech required. And make one Psalm-code can be included into two different doctrines and count for both.