Google, then click on website, sends me to a random site

This is really annoying and I don’t know why it is happening. Can Avast fix this? Please help.
Happens every single time. I will click on a website to go somewhere and then it will redirect me to some shopping site or survey site. Cannot hit “back”…doesn’t work. Only way is to paste the website address into the browser manually.

Check your computer for Malware with

Malwarebytes Antimalware http://filehippo.com/download_malwarebytes_anti_malware/
after install click UPDATE and run quick scan, click on REMOVE SELECTED to quarantine anything found

SUPERAntiSpyware http://filehippo.com/download_superantispyware/
Are cookies really spyware and are they dangerous?
http://www.superantispyware.com/supportfaqdisplay.html?faq=26

If anything is found come back and post the scan logs here

May because of your hosts try doctor web cure it make express scan at the end it will suggest REPAIRING THE HOSTS FILE