Hello Dave.
From your description, we assume that you're referring to a search engine of your web browser.
Initially, please reset the web browser on which you're facing this issue & check if the issue persists.
Refer to this article (https://support.avg.com/SupportArticleView?urlname=AVG-Reset-browser) to reset your web browser.
Keep us updated.
When I do a search in Google Chrome it is redirected to yahoo and results are from opera.
Hello Dave.
From your description, we assume that you're referring to a search engine of your web browser.
Initially, please reset the web browser on which you're facing this issue & check if the issue persists.
Refer to this article (https://support.avg.com/SupportArticleView?urlname=AVG-Reset-browser) to reset your web browser.
Keep us updated.