In https://koha-community.org/manual/latest/en/html/webservices.html#sru-server this URL makes references to a real library! It must be fixed "My search for http://univ_lyon3.biblibre.com:9999/biblios?version=1.1&operation=searchRetrieve&query=coral reefs&maximumRecords=1 retrieves just on record. The response looks like this:"