You can now search your [url=/mycollection]collection[/url] and [url=/mywantlist]wantlist[/url]. There is a search field at the top of those two pages.
Please note that this is somewhat experimental right now. There is a limitation that you need to use a more precise search on your collection/wantlist. Without getting too technical, searches like “records”, “remix”, and “style:techno” are too general and we can’t efficiently compare the results to your collection/wantlist. In cases like these just add one or two more search terms to your query and that should work. I hope to get over this limitation at some point.