Be sure to bring your resume when looking for a job! But don't bring a cover letter! But it's better to take it than not to take it! Generally, cover letters are handed in at the back of your resume!

A resume is a written form that shows your educational background, specialties, abilities, etc. It's the way the company gets to know you for the first time. Its quality is related to the quality of the first image. Therefore, it can be appropriately exaggerated. And the letter of recommendation is to show your sincerity. Personally, I think a cover letter is a polite expression! Not much use.

Now the units are very practical, what they want is your education and ability!