So Firefox has been defaulting to Ask.com as my search engine at work, which for whatever reason really bugs me. Similar is happening home but I think it is that crazy duckandgo which simply finds a lot of crap.
To change this it is necessary to navigate the keyword URL field of options, but not via a GUI. Use the about:config method by entering that in the address bar. Firefox will ask if you are sure you want to navigate to this page as it impacts core settings. You do!
With about:config loaded, you can search for the appropriate field by enterring “keyword” in the search box.
Double click the value of the keyword.URL
Replace the Ask address string with the equivalent google one : https://www.google.ca/search?q=
Or whatever is your preferred search engine and the result should be quite wonderful, google searches by keyword from the address bar forever more.