A technique I use for serendipitous resurfacing in Zettelkasten-like systems is to make it a daily habit to review some cards at a set time. This time and the amount of cards may vary–beginning of the day, during lunch, or at the end of the day.
I feel like its more important to keep the habit than to be a stickler about specifics. As long as I get it done and keep the streak going, I consider it a win.