Clarify the "Check to match ANY; uncheck to match ALL"

Hi,

Report from the users on the advanced search on custom fields that have multiple values (checkbox or multi-select): The feature is great, the UI is confusing. Several issues pointed out:

1) it's not clear that it changes the behaviour of the search, as it's simply another checkbox, it looks like it's one of the possible values
2) The text is super long (even more when translated, in dutch for instance "Vink aan om te selecteren, of vink juist niet aan om niet te selecteren.")
3) when you have a A/B option, using a checkbox is a bit of an anti-pattern (check if FEMALE, uncheck if MALE

Suggested solution: replace the checkbox by a "match" select with two values : "ANY & "ALL"
I'm wondering if it wouldn't be nicer to put on the 1st column, right next to the label of the field instead of after the value.

@Dave, what do you think? Does it make sense?