Eric, don't forget that only 48% of your large collection of cookbooks are indexed. So there will probably be cannele recipes in your unindexed books. If the entire EYB library has 29 cookbook recipes for cannele and you are seeing 22 recipes in your collection then your search seems to be correct. You just are not seeing the recipes in the unindexed books.
A fix for this, though maybe not practical given the size of your collection, is to look at the back-of-the-book indexes in your unindexed French cookbooks - you can see them in this search - then index the cannele recipes as Personal Recipes. You would enter the book title and page number in the source field. Then when searching for cannele recipes you will see every cannele recipe in your cookbooks, even the unindexed ones.