BGA Feature #60 Game Search Filter to Exclude Expanions
I can't remember where or by who this was mentioned, but someone was looking at the search and sorted the games by score and noticed that most results were expansions for games and wanted to filter them out. That is now an option! If you look at the filters section you can see a new checkbox under the playtime.
You may notice that there are games that are expansions still showing in the results. That means that they haven't been connected to their base game yet and needs to be connected. You can do that yourself if you'd like since this database is a wiki style community supported one. Just go to the base game page and then scroll to the "expansions" section and click the + sign to add in the expansion game page's link and it'll connect it up!