NEVER say 'I can't find my...'
Instead, say 'I'm looking for my...'
The first comes across as a whinge. It's a statement of inaction. You can't find it. You've given up all hope. You've stopped looking. Oh well. If the situation is that bad, you might as well get busy to take your mind off it. Here. Take out the rubbish.
The second is winsome. It implies action. I was going to ask you to take out the rubbish but won't because you are already busy. Good kid.