Use Google Hacking Database:

https://www.exploit-db.com/google-hacking-database

Search public informations about LDAP connections

"ldap://" site:<domain>

Search for sensitive IT credentials:

"password" "credentials" "login" "access" "vpn" "active directory" "ldap" "auth" "authentication" "token" "secure" "key" "encryption" "account" "admin" "username" "user" "login details" "root" "database" "sql" "config" "configuration" "setup" "default password" "network" "remote" "rdp" "ssh" "openvpn" "pptp" "ipsec" "secret" "authorization" "directory" "group policy" "domain" "firewall" "proxy" "server" "privilege" "privileged" "backup" "hash" "md5" "sha1" "sha256" "access control" "acl" "kerberos" "ntlm" "plaintext" "plaintext password" "hashed password" "cracked password" "site:" "filetype:" "doc" "docx" "xls" "xlsx" "pdf" "txt" "log" "conf" "ini" "cfg" "xml" "json" "yaml" "azure" filetype:log filetype:pdf filetype:doc filetype:docx site:<domain>

Search for classified documents:

site:*.domain.it "classification: sensitive"