patch up vs touch on

patch up and touch on both are verbs.

Word	Noun	Adjective	Verb	Adverb
patch up	No	No	Yes	No
touch on	No	No	Yes	No

As verbs, touch on is a hypernym of patch up; that is, touch on is a word with a broader meaning than patch up:

patch up: mend by putting a patch on
touch on: restore by replacing a part or putting together what is torn or broken

Other hypernyms of patch up include bushel, doctor, fix, furbish up, mend, repair, restore.

patch up (verb)	touch on (verb)
mend by putting a patch on	restore by replacing a part or putting together what is torn or broken
come to terms	have an effect upon
	refer to or discuss briefly
	be relevant to