If Rick has the letters, he's too smart to let you find them there.
4 seconds sound clip from the Casablanca (1942) movie soundboard.
You can hear this line at 00:51:09 in the Blu-ray version of the movie.
Quote context
[...]
- I guess neither one of our stories is very funny.
- Tell me who was it you left me for?
- Was it Laszlo, or were there others in between or aren't you the kind that tells?
- I strongly suspect that Ugarte left the letters of transit with Mr. Blaine.
- I would suggest you search the café immediately and thoroughly.
- If Rick has the letters, he's too smart to let you find them there.
- As to Laszlo, we want him watched 24 hours a day.
- It may interest you to know that at this very moment he's on his way here.
[...]