Because writing this type of letter takes time, it's a good idea to only send cold contact cover letters to companies that you are very interested in working for. (thebalance.com)
On top of that, I had to convert a number of cold contacts into regular sales and customers. (anfieldindex.com)
In a nutshell, targeting a company for a job when the company does not advertise their vacancies is called as cold contact approach. (readresume.com)