Care packages for navy sailor on a ship.

It’s been a month since my boyfriend left on deployment and I’m planning on sending hkm a care package but I don’t really know what to send him besides can’t and snacks he miss from here. Can I send like NyQuil and DayQuil in case he gets sick or something? I know there restrictions on what you can and can not send but do they open it up and check or something? Can you guys give me tips on what to send because I’m not sure what they need on a ship