Opera Mail searching for attachment names?

I just switched and it appears that there is a limitation that is going to be a problem for me. I regularly send invoices that are numbered and named i.e. "1253.pdf". Is there any way to use the opera mail search to look to see if it was sent? I tried it and it appears to scan the content and title only and I need it to search for attachment names. Is there any way to do this?
Also is there any way to search sent and received emails at the same time?

Opera doesn't seem to index attachment names. You can't even search for them by using the "entire message" rule for a label.

But, there are 2 workarounds I can think of atm:

* When there's a file attached to a message, it's often polite to mention it in the message.

Examples:

"Attached is 1253.pdf. It contains your invoice."

"Your invoice is attached as 1253.pdf"

So, if the filename is included in the message or in the subject as "Your Invoice (#1253)" for example, you'll be able to search for the message a lot easier.

or

* Create a label named "Sent Invoices". Open its message list, click the view button above the message list, goto "show" and check "show sent". Then, whenever you send an invoice message, after it's sent, goto "All Messages/Sent" and apply the "Sent Invoices" label to the message.

That way, you'll have a view for only sent invoices which will make it a little bit easier to find the one you want. But, if they all have the exact same subject and you have a lot, you'd still need to tag the subject or body with text containing the file's name so you can search.

Note that if you want attachment filename search in Opera, you can ask for it in the wish-list forum.