The relevance you have provided is not quite correct for what you want. That relevance would filter out all computers that have that KB installed.
This seems like what you are looking for:
exists (string values of properties "HotFixID" of it) whose(it starts with "KB2511455") of select objects "HotFixID from Win32_QuickFixEngineering" of wmis
This topic/post is a duplicate of: Need analysis Fixlet for Particular KB number based report