I tried this. With the word "British," the first two pictures were David Cameron and George Osborne, and the next was Boris Johnson. When I took out "British," I got some drawing of a politian stabbing another one (?), followed by some fat presumably American guy I don't recognise, then Joe Biden. No Trump or Clinton!
I have noticed that when using UK Google, which I bookmarked, as opposed to the default Google that used to be in my phones browser, I got different results. Also, I was using regular Google, not Google images. Were you using images?