Man pages matching name gnutls_ocsp_req_set_nonce in section 3:

gnutls_ocsp_req_set_nonce.3.en	debian 10 / gnutls-doc
gnutls_ocsp_req_set_nonce.3.en	debian 11 / gnutls-doc
gnutls_ocsp_req_set_nonce.3.en	debian 12 / gnutls-doc