tea leaf vs tea bag

tea leaf and tea bag both are nouns.

Word	Noun	Adjective	Verb	Adverb
tea leaf	Yes	No	No	No
tea bag	Yes	No	No	No

As nouns, tea bag is a hyponym of tea leaf; that is, tea bag is a word with a more specific, narrower meaning than tea leaf:

Other hyponyms of tea leaf include black tea, green tea, oolong.

tea leaf (noun)	tea bag (noun)
dried leaves of the tea shrub; used to make tea	small paper bag holding a measure of tea
	a measured amount of tea in a bag for an individual serving of tea