The DR number, Diederich Rank, refers to the highest number in Diederich's frequency listing, which you can see here: Diederich Ranking.
DR 82. Audientes non audiunt. ~ Note: The words are from Matthew 13, and it is also included by Polydorus in his Adagia, B342.
DR 82. Cum dixeris quod vis, audies quod non vis. ~ Note: Note the nice parallel structure: dixeris/audies and vis/non-vis. You can find a similar saying in Erasmus's Adagia, 1.1.27: Qui quae vult dicit, quae non vult audiet.
DR 83. Pars est in toto, totum non est in parte. ~ Note: This is a Latin legal maxim which can be applied to many aspects of life, of course.
DR 84. Qui habet tempus, habet vitam. ~ Note: This is a medical principle, the idea being that with time, an ailing person can hope to recover - an idea that can be applied, metaphorically, to all of life's difficulties.
DR 84. Tota hominis vita, unus est dies. ~ Note: Note how the predicate phrase, unus dies, wraps nicely around the verb.
DR 87. Bono animo esto. ~ Note: Here you see the future imperative esto used with an ablative predicate, the so-called "ablative of description" or "ablative of quality." In English we might say: Keep a positive attitude!
DR 87. Bonum habe animum. ~ Note: This good advice shows up in Plautus's play, Captivi.
DR 87. Bonus esto bonis. ~ Note: You can find this advice in the dictichs attributed to the so-called Cato: Sic bonus esto bonis, ne te mala damna sequantur.
DR 87. Cui bono? ~ Note: This famous double-dative proverb expresses the idea that if you want to know who did something (in particular, if you want to know who committed a crime), then you should ask who benefited from it. For an example from Roman oratory, see Cicero's speech Pro Roscio.
DR 87. Bonis omnia bona. ~ Note: This is the motto of the Orr family. Note that you see here the adjective bonus used substantively to refer both to people (bonis, for the good people) and also to things (bona, agreeing with omnia: all things are good).