Là, tu cherches la petite bête.
Lah, tew shairsh lah pteet BETT. Click below to hear this!
Now you’re splitting hairs.
English speakers split hairs, but French speakers look for the little critter. Bugs, most likely! Il y a des petites bêtes ici ! generally means There are bugs here! Une bête is a beast or a critter, but if it’s petite, chances are it has six or eight legs, and not just four.
So when you say Là, tu cherches la petite bête, you are accusing someone of focusing only on irrelevant details and not seeing the big picture, the more important point.
Bête also means stupid, dumb, but it’s no more polite in French than in English to call someone bête. You are not, however, prevented from using the word to describe yourself, as in Qu’est-ce que je suis bête ! (KESS-kuh zhuh swee BETT, How stupid of me!