Say you are writing LotusScript and declare a variable like
Dim doc as NotesDocument
Then later in the code you want to instantiate it and write
set doc = new ...
The classes hints list starts with "NotesACL" and lists all the possible classes available. But you've already declared the variable so Designer should already know what the type is. The hint should instead land on the type defined earlier so all you have to do is press Return to select it.