I think i figured what the problem was.
Not an issue with ST.
Actually what seemed to happen is, when i wanted to press 'ctrl + f' and then 'enter' to find the first instance of the string. I accidentally pressed 'ctrl + enter' which caused the find bar to take a new line character. The text that was entered in the find bar was essentially out of view because of the new line character, due to which i would enter the search text again and sublime text would not find that text which ended up being "search string\nsearch string".
Checkout the below screenshot, you will notice some portion of previous line in the search box (which i thought was an drawing issue).
Thanks and Regards