Finding Company Contacts Without LinkedIn URLs: Best Methods

hey guys, what's the best way to find people in companies if I have a table with company names and urls? tried to use "Find people" hoping to find people within the companies, but there are always people from Microsoft, Google and other companies that are not in the list. When I search by company Linkedin URL, it works. But I don't have Linkedin URLs for the companies. I know I can enrich, but 16K is too much