The case of Abela v Baadarani confirmed that the courts will grant a search order against any person (not just someone that is an actual party to the court proceedings) who holds evidence that is or might be relevant to the claim, where the order is made for the purpose of securing that evidence. There are other routes to obtain documentation from third parties (such as a Norwich Pharmacal order, under a particular English court rule called CPR 31.17, or by a witness summons), but where there is a risk that the evidence will be destroyed or concealed by the third party, the court has the power to grant a search order.
This is an incredibly useful tool if you suspect that there is someone conspiring with the fraudster to destroy or hide evidence.