It is not possible for anyone to block access to https://www.google.com/?q=specific+thing over a long period of time without either custom modifications to every affected client or help from Google itself.
Google's long rocky experience with China proves exactly that.
Not at a 100% level, but we know the Chinese government (and I suspect the UK government) are capable of deploying faked google.com SSL certs which'll pass unnoticed by just about anyone who's not using a certificate-pinning version of Chrome. And China(/Iran/Egypt) clearly has national-border level firewalls capable of using such faked SSL certs to MITM and deep packet inspect entire countries worth of internet traffic on the fly.
Google's long rocky experience with China proves exactly that.