After a long time of illogical brainstorming, I finally got to know why form validation was not working in CodeIgniter (in one page.
You can see the question over here.
What actually happened is while declaring the rules for the validation, instead of writing field, I wrote name.
Just this much and my code started working. Now I am over to the next portion which is developing a search.
Also, yesterday I started using TiddlyWiki. It is a really nice thing to stored your journals. Try using it once for sure.