Green’s Dictionary of Slang

turn up v.4

[? SE turn upside down]

(UK/US) to search.

[UK]Clarkson & Richardson Police! 295: Her domicile was also ‘turned up,’ but no trace of the notes could be found.
[Aus]Crowe Aus. Sl. Dict. 89: Turned Up, to be searched by the police.
[US]F. Williams Hop-Heads 40: Hands off her. You want her turned up?