Is it possible to add a custom keyword to the intelligence trainer?

Say I want to add a specific feed, but I care about nothing except for stories with a specific keyword (that has not yet appeared in the feed). Can I type the keyword into the intelligence trainer?

Example use case (not mine, but a quick one I thought of): Say you want to prioritize all stories with the phrase ‘Halo’ in reddit.com/r/games and you care about nothing else in /r/games. It would be beneficial to add /r/games to your feed, de-prioritize everything from the site, then prioritize everything with the keyword ‘Halo.’