Search not working on a theme converted from hexo

Hi Guys I tried to replicate the Hexo Document Theme (here)

All went fine until I tried replicating search functionality from there. It seems to use lunr.js and it seems to read from a json file.

Whatever I search I get “There are no results for” followed by the search term, I entered. This is the default message given in the doc.js file when its not able to find any result.

I tried to see if the location of the JSON file is the cause. I am not sure what I am missing. Please help.

I zipped the project and uploaded here

Can somebody help me find out what I have missed. Thank You very much.