I have no idea what you mean by "i tried everything on my hands to change it because i am tired of the silly redirects but i failed."
Without knowing what you tried how can anyone really offer any suggestion, but here goes.
1. Did you click on the magnifying glass icon in the search area ?
You should have a number of search engines there you can select as the default.
2. If what you want isn't their, how about the Change Search Settings below those other options ?
That gives you more options and there is also a 'Find more search engines' option if your engine of choice isn't there.
3. of course there is always using the search function
To find how to change the default search engine in Firefox.
However what you don't do is say what Firefox version you are actually using as these settings could change between versions.
You have to help us to help you