Ajax is so popular nowadays so you should learn how to mimic it in your web crawler.
In this exercise, try to extract the product detail such as title, desc, and price.
You should learn how to inspect network requests in the browser and filter them, after you figure out the URL of the ajax request, implement it in your spider.
Web scraping using XPath or CSS expression
Load JSON string and extract data
Not only crawl products but also handle pagination
Inspect Ajax requests and mimic them
Learn to inspect the fields of HTTP request
Learn to scrape infinite scrolling pages
Make your spider can work with the cookie
Scrape data behind login form
Learn to scrape data behind a captcha