The other option would be use to
https://www.startpage.com/ which also uses google to get results. However, the drawback here is that you will not get your searches optimized for your geographical location. The other drawback is that search results will also be given without your previous search history in mind. Google is very good at what it does takes those and other things into consideration when it spits back the results. However, some might also consider these things a plus and not a negative. If you don't trust startpage's results do a side by side comparison using the exact search terms I think you'll find that they are pretty close.
Also keep in mind that depending on your settings Firefox will also do a auto-complete or suggestion terms based on your history.