Much like any other Windows application, GoldMine keeps track of the last items you've been working with. In GoldMine's case, it tracks the last few viewed Contacts along the left hand side of your screen. However, it comes "out of the box" only tracking the last five.
To increase this value;
1. Select Tools | Options | System tab
2. Under Navigation, increase Recent items shown to 99 (the maximum)
3. Restart Goldmine
This happens on a per-user basis. Anyone who wants their recent Contacts list to be 99 lines long will need to do this.