If you add UK to the end of the most affected 2 word term in my niche you get much better results
I have noticed this for quite some time for my UK widgets.
For instance keyword1keyword2keyword3 shows nearly all Chinese and Indian directory sites with a couple of genuine original widget manufacturers, however adding UK myself and .co.uk sites suddenly appear.
When I realised this awhile back I left my main .com site as was and doing well globally BUT not in the UK, upped my .co.uk sites and now they're pulling in more traffic.
What I do not understand is why G has done this solely to the UK SERPs since my .com has been registered and hosted in the UK since 1994 but now seemingly has no relevance for the UK results whereas Chinese and Indian directory sites do.
Oh, and a US .com who has no chance in hell of supplying the UK also features in the UK results.