Agreed, though enabling searches of such depth might create a considerable computing overhead. For example, there are lists of cities by population for most co

Agreed, though enabling searches of such depth might create a considerable computing overhead. For example, there are lists of cities by population for most countries; if you could manually select a subgroup for -a- country and submit that as a search group along with other terms, might be within reach ... but to do that for -all- countries, imagine the complexity. Maybe when WP gets a few more million-core supercomputers. On the other hand, that would be a -great- project for some enterprising startup.