The query has to be analysed and cannot be mapped simply to the title index. That means that the query above has to be transformed conformant to our server and cannot be rejected with the message 'unsupported attribute' because we don't have such a search key. Another possibility to act more or less smart as target is again the attribute mapping. Even if the client has an idea about the differences of these attributes a server may just have a name index with all the author and personal names in it. It would be the best guess to map any of these attributes to this index.
Many servers have a basic index for the default search.
But very often the indexing of a server is restricted to a specific search type, e.g. word list. Even if you found out you will probably look to hide specific behaviour of servers to the user. A possibility here is to tailor the queries before submitting them according to specific server needs. This means to add 'intelligence' to your client. If you got a client that does not support a functionality you need to make benefit of server functionality you will probably replace it by another.