Does you user category have subcategories? If the user category has subcategories then @category:true and @category:false find only the items in the first level. The subcategories are ignored. If you want the category and all of its children, use @category:.true and @category:.false. Just as in hierarchical columns, the '.' tells calibre to include the children.
Does you user category have subcategories? If the user category has subcategories then @category:true and @category:false find only the items in the first level. The subcategories are ignored. If you want the category and all of its children, use @category:.true and @category:.false. Just as in hierarchical columns, the '.' tells calibre to include the children.