Official Member of the Mean Girls Cult
They do search the bags you drop off. I had an item removed that wasn't allowed - a power strip which I've packed on several prior cruises and that's the first time it was removed from my luggage. But it was returned when we got off the ship. It delayed that bag being delivered to our room. Live and learn.Just to add to this, as the OP is a first time cruises. This is nothing like checking your bags at an airport. DCL has sent you tags for your bags with your room number on them. You put those on the bags you are going to drop off. DO NOT PUT THINGS LIKE YOUR ID, OR MEDICATION, OR ANYTHING IMPORTANT IN YOUR DROP OFF BAGS. Once you drop them off, you are not going to see them again until they get delivered to your stateroom. If you put your passport in your drop off luggage, then you are not getting on the ship (at least not without a MAJOR hassle).
Now, you have your tags on your bags to drop off, and nothing important in them. When you pull up to the curb, there will be a bunch of DCL workers there with luggage carts. they will take your bags, give them a cursory glance to make sure you have tags on them, throw them on a cart, and then .... that's it (It is nice to tip them). There is no receipt, there is no scanning of your document, there is nothing like that. You give them your bags, and you go away. Do not worry. This is how the process works, for all cruises,. and it works well. Your bags will show up at your stateroom as long as you put your tags on them.
It can be disconcerting for first time cruisers who are used to all that goes with checking bags at an airport.