reading vs studying

reading and studying both are nouns.

Word	Noun	Adjective	Verb	Adverb
reading	Yes	No	No	No
studying	Yes	No	No	No

As nouns, studying is a hyponym of reading; that is, studying is a word with a more specific, narrower meaning than reading:

reading: the cognitive process of understanding a written linguistic message
studying: reading carefully with intent to remember

Other hyponyms of reading include speed-reading, perusal, perusing, poring over, browse, browsing, skim, skimming.

reading (noun)	studying (noun)
the act of measuring with meters or similar instruments	reading carefully with intent to remember
the cognitive process of understanding a written linguistic message
a mental representation of the meaning or significance of something
a datum about some physical state that is presented to a user by a meter or similar instrument
written material intended to be read
a particular interpretation or performance
a public instance of reciting or repeating (from memory) something prepared in advance