I agree, that's pretty annoying, though likely gnome's / Ubuntu's fault more than Zorins's. But if Zorin can fix it within their OS that would be great. I had a similar frustration that Thunderbird doesn't show when you type "email" but does for "mail"
As a more immediate solution, try software called Menu Editor, which allows you to edit a "keywords" field and I can report (on Fedora Workstation which uses mostly vanilla gnome) that typing "notepad" does bring up the Text Editor.
I tried the same program (or it looks extremely similar) called "Main Menu" in Zorin. I have tried to edit it, and i hit OK but it just doesn't OK it. The button flashes, but it doesn't OK. The box stays up.
The solution is to add a keyword as mentioned by @Ultrabenosaurus above. However, if the Menu Editor doesn't work, you can skip the middle man and edit the .desktop entry for this program directly.
Open the file located at /usr/share/applications/org.gnome.gedit.desktop. Add a new keyword accordingly on the "Keywords" section. Make sure to end the line with a semi-colon (;)