Add Missing Cards

When I am adding my cards to my collection, sometimes the card won't be in the system so I can't add it. It would be nice to be able to add to the system, even if it means it needs to be verified or something. 

for example- the cards I collect are numbered and I physically have 118, 119, 220, however when I go to add 119 that card isnt on the app at all. If I could add to the system/app that'd be super helpful.