Quick workaround for now, if you haven't already done this:

Go to the vocab page.

Open the drop down "Action"

Select "Edit Page Length". (Yes, that really should be put into "Settings". I only found it by accident too.)

Put in 1000 or 2000 or something like that.

Now you get the entire vocab list on a single page and you can use the search function in firefox or chrome or whatever to find the word you are looking for.