Hi,
Without knowing what your documents are and going by what you wrote, if they are invoices, the best way to check is contact the supplier directly and confirm the invoices. Contact the accounts department or section and ask for the section/department manager and they will take it from there.
This will be effective if the organisation is a large organisation, but if it is a oneman show, then what about the services/products received by your entity, can anyone confirm receipt of those services or products?
I hope this helps.