You can search multiple keywords with something like this:

    label:robotics + label:machine_learning

in the author search. Narrowing by country can be trickier. You can potentially narrow by the email address. For example, if their profile is verified with a UK email address it will end in `.ac.uk.` Thus you can search:

    label:robotics + label:machine_learning + .ac.uk

and only get UK researchers. You'll probably get some false positives and negatives with this technique so it's not perfect but will help narrow the scope.

Here's a related question pertaining to narrowing country on Google Scholar:

http://academia.stackexchange.com/questions/59681/google-scholar-how-to-exclude-some-countries-from-the-search