The autocomplete function in canvas is great. In the peoples' area you can type in name, sis id, login id and the list reacts and shortens to the people you really want to see. This function saves time, reduces stress and any potential confusion.
However . . .
This is not always across the board. In the release notes Canvas Production Release Notes (2018-02-17) the email tool now allows you to autocomplete on the course title, but not on the course code. Students like the course title because it is easier to remember, academics use the course code, because they may have more than one research module.
What if we had a little rule that any canvas autocomplete searches should attempt to reference as many fields as possible? Then the user would never wonder why a particular thing they have types had returned not found. And all would be right with the world!