Man pages matching name gnutls_pkcs11_get_raw_issuer_by_subject_key_id in section 3:

gnutls_pkcs11_get_raw_issuer_by_subject_key_id.3.en	debian 10 / gnutls-doc
gnutls_pkcs11_get_raw_issuer_by_subject_key_id.3.en	debian 11 / gnutls-doc
gnutls_pkcs11_get_raw_issuer_by_subject_key_id.3.en	debian 12 / gnutls-doc