printing business vs printing concern

printing business and printing concern both are nouns.

Word	Noun	Adjective	Verb	Adverb
printing business	Yes	No	No	No
printing concern	Yes	No	No	No

As nouns, printing business and printing concern are synonyms defined as:

printing business and printing concern: a company that does commercial printing

Other synonyms of printing business include printing company.

printing business (noun)	printing concern (noun)
a company that does commercial printing	a company that does commercial printing