Trouble searching for credit card / bank account numbers

Wow, volts, great sleuthing, thank you for figuring that out! Yes, for me to it seems that this is what's going on.

I'm noticing some difference in behavior between banks accounts and credit cards.

For credit cards:
- If it is stored as 1111222233334444, no spaces, then a search for "4444" will show up only in the dropdown search list, but not in the "Show All Matching Items" list when I hit CMD-Enter. As I pointed out in my first post, this is totally weird and cannot be the intended behavior; right??
- If it is stored as 1111 2222 3333 4444, with spaces, then a search for "4444" will show up in both the dropdown search list, and in the "Show All Matching Items" list when I hit CMD-Enter. This is the expected behavior!

For bank accounts:
- If it is stored as 1111222233334444, no spaces, then a search for "4444" will not show up anywhere.
- If it is stored as 1111 2222 3333 4444, with spaces, then a search for "4444" will show up only in the dropdown search list, but not in the "Show All Matching Items" list when I hit CMD-Enter. Notice that this is akin to the behavior for a credit card stored as 1111222233334444. So even the weird behavior is not consistent between different item types.

And besides, bank account numbers are not usually presented with spaces, so I never enter them with spaces. Despite this, it is often useful to be able to identify bank accounts by their last four digits.

I, too, deeply hope that substring search returns!