Premade charm square packs from the manufacturer (like Moda) usually have 1 of each print in a line (depending on the # of prints in the line, there may be some duplicates). Since the line normally includes blenders and/or solids along with the prints (small, medium and/or large scale prints), these are included the charm packs.
If you're wanting specific prints like flowers only, you'll probably have to make your own or find someone who makes their own and sells them on a site like eBay.