It won't save everything, but if a script follows every link recursively, most content should be reached that way. That's kind of what Google does but for one site instead of the internet.

If there is a search function try very simple queries.

The alternative of brute forcing links would be unfeasible, even if you are not rate limited by the site, due to the exponential complexity.

If you want to do something please look into api/scraping etikette like exponential back off.