Links are not crawlable

i do scan with the PageSpeed Insights and say
“Links are not crawlable”
“Search engines may use href' attributes in links to crawl websites. Make sure the href’ attribute of the anchor elements binds to an appropriate destination so that more pages of the site can be discovered.”

The link of google is:

Why can’t crawl bots crawl my site? And how do I solve the problem?
Search engines have indexed a large part of the web, but not all of it.
You can help?