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:
Google Scholar: how to exclude some countries from the search?Google Scholar: how to exclude some countries from the search?