Private investigation firms in Lodz?

Can anyone suggest a name of a reliable private investigator in Lodz. I need help locating a person that currently lives there, and i only know his nickname. I can not make a contact myself as I tried all avenues. I emailed few listed private investigators in Lodz, but no one cares to respond for some reason!?! I am not sure about making a phone call to listed numbers of these agencies, as they might not speak English, and I do not speak Polish. If someone had used services of this kind, how expensive these services are? It should be 1-2 days work for a professional. I will be traveling soon to Lodz from New Zealand and ideally I would love to have details of this person given by than

Thank you in advance

Call them, they could think that emails in English are not serious. You will not know if they speak English until you try

If you have cash you can first employ a translator and ask him to do the calling for you

Thank you for your response, i tried to call twice, and as soon as someone there heard my English immediately disconnected. That is a recipe for doing bad business in my books, and feeling so disappointed