build a crawler (data crawling) for pdf document

We are interested in having someone make a crawler (data crawling) chrome extensions mainly used for pdf documents to crawl keywords for us. The difference with the ordinary control F is that this crawler needs to find the number of occurrences of keywords specified by the user in a particular section (e.g., pages five to ten); fuzzy query function; statistics of keywords appearing in the document more than a specific number of times (the number of times specified by the user). The best final result can be displayed on the web page, as the page's layout only requires beautiful and no specific requirements.No matter what language you use if you can finish it perfectly.