Textual search support

Sorry if such a topic already exists.

Having entire pieces encoded in xml (text) format I would offer the possibility for searching on musical themes, rithms or maybe even something else (accords). As far as I know the current format of the xml (the predefined xml tags) does not support extracting significant elements of the sheet in the header something like:

Fur Elise (without modifiers, just for simplicity):
<themes>
<theme>E D E D E B D C A</theme>
<theme>C F E E D B A A G F E D C B A</theme>
</themes>

This might be too restrictive, as one must know the exact signature of the piece --> a relative notation might also be useful (or even more useful):
<themes>
<theme>V IV V IV V II IV III I</theme>
</themes>
(where I means tonica).

Bolero
<themes>
<theme>4 888 4 888 4 4</theme>
</themes>
(where 888 means triolet)

Anyway, something representative for that song so that anybody loking for the staff of a piece edited with MuseScore can type into Google the theme he is interested in.

What do you think: might this be a useful feature?

Best regards,
Istvan