A Google Books search shows a few other uses of the term in the Bulgarian/Macedonian literature of the period describing the Ottoman Macedonia of the day. Vasil Kunchov explains (Macedonia, 1900, page 135):
At the birth of every child, a certificate called "nofuz" is issued by the government, via the ecclesiastiscal authorities. In it, the child's sex, name, birth date, birth place, and the names of the parents are recorded. The nofuz certificate is needed by every Turkish subject, because without it one cannot travel within the country or receive a passport to travel outside of it; without it, ecclesiastical authorities must not issue a marriage license. This being the case, everywhere in Turkey there are plenty of men and women without nofuz certificates.
... Нофузното свидетелство е нужно на всеки турски подданикъ, ...
And here's a good article in English on those IDs: Ottoman Identity Card, by Chris Gratien, with a few photographs of what those documents looked like. It turns out that in Turkish they were called nüfus tezkeresi, where nüfus by itself means, apparently, "population". It seems that in the Slavic language of the day the colloquial name for the document became shortened simply to nofuz.