Searching using/in URL bar

1. Go to any site which you use for searching (e.g. Wikipedia).
2. Right click on text box where you enter your query.
3. Click on "Add a keyword for this search".
4. Enter <keyword>(e.g. wk) in keyword box.
5. Save.

Whenever you want to search 'something' in Wikipedia, just type 'wk something' in URL bar. If search doesn't work, try to analyse and modify location field.