Not sure which strokes you are interested in, but we have a popular video series with Kristy Kowal with some great breaststroke drills to try. Or you can check out our library of drills on Swimspire, where freestyle is predominant. Here are the links to both:
Video collection: www.swimspire.com/videos/
Kristy Kowal: www.swimspire.com/breaststroke-drill-video-series-olympian-kristy-kowal/