F1-OPT Status. Could I deduct job search expenses? Where should I put this on the 1040nr? Is there a for to itemize this ?

No.
Read: Your U.S. Tax Return: U.S. Tax Filing Requirements for Non-Residents

Actually, you CAN claim job search expenses on Form 2106 with the final figure being entered under Miscellaneous Expenses on Schedule A. You have to exceed the 2% rule, but if you are mandated to itemize, that should not be an issue.