come across vs attain

come across and attain both are verbs.

Word	Noun	Adjective	Verb	Adverb
come across	No	No	Yes	No
attain	No	No	Yes	No

As verbs, come across and attain are synonyms defined as:

Other synonyms of come across include chance on, chance upon, come upon, discover, fall upon, happen upon, light upon, strike.

come across (verb)	attain (verb)
be received or understood	reach a point in time, or a certain state or level
communicate the intended meaning or impression	reach a destination, either real or abstract
come together	find unexpectedly
be perceived in a certain way; make a certain impression	to gain with effort
find unexpectedly