go over/through something with a fine-tooth comb
US /ɡoʊ ˈoʊvər/θruː ˈsʌmˌθɪŋ wɪð ə faɪn-tuːθ koʊm/
UK /ɡoʊ ˈoʊvər/θruː ˈsʌmˌθɪŋ wɪð ə faɪn-tuːθ koʊm/

1.
passer au peigne fin, examiner minutieusement
to examine something very carefully, looking for mistakes or problems
:
•
The auditors will go over the accounts with a fine-tooth comb.
Les auditeurs vont passer les comptes au peigne fin.
•
We need to go through the contract with a fine-tooth comb before signing it.
Nous devons passer le contrat au peigne fin avant de le signer.