The search query you've provided——is a specific type of search string known as a "Google Dork." In the world of cybersecurity, these queries are used by security researchers (and unfortunately, bad actors) to find specific vulnerabilities, misconfigured servers, or leaked files that have been indexed by search engines.
By understanding how hackers use these specific search strings, you can better defend your digital footprint from being the next "dork" result. intitle liveapplet inurl lvappl and 1 guestbook phprar
Your original query included guestbook.phprar . This is highly anomalous. In standard Linux/Unix file systems, a file cannot have two extensions in a way that changes execution priority. However, an attacker might use this string to test for: intitle:liveapplet inurl:lvappl and "1 guestbook