Like Rachel, the patriarchs were shepherds. One thing the patriarchs never quite accomplished was  farming  the land  to  produce grain, wine, and  oil for tithes and offerings.  They were shepherds.  Only Isaac  briefly settled toward the fertile plains north of  Be'er  Sheva, and he planted one crop .  Wine and oil require long-term cultivation. Grain, wine, and oil tithes culminate at Sukkot, or the Feast of Asif.  Asif shares the Hebrew root of Yosef .  Yosef dreams of a time when grain will provide bread for Israel to fulfill the promises to Avraham, Yitzchak, and Yaakov.

"...for  behold, we were binding sheaves in the field, and lo, my sheaf rose up and also stood erect; and behold, your sheaves gathered around and bowed down to my sheaf ." (Ge 37:7)

Yosef's grain prophesies of an  exile in economic prosperity . Yaakov had an exile of economic prosperity in Aram, but then he realizes  Lavan  intends to take everything he's earned. Likewise, the wealthy Hebrews are reluctant to leave Egypt, then Yosef's other dream activates. The Hebrew are subjected to the astral deities of Egypt as slaves to Pharaoh's demonic building projects: 

'Lo , I have  had  still another dream; and behold, the sun and the moon and eleven stars were bowing down to me .' (Ge 37:9)

Economic prosperity was actually an exile that led to harsh subjugation to the gods of Egypt, an  exile of affliction . Two dreams, two kinds of exile.

Yosef dreamed of sheaves of grain. Not since Isaac's youth had the patriarchs planted a significant field.  The text gives the brothers' and Yaakov's interpretation of his dreams, but the dreams were not just youthful narcissism. They were prophecies of exile, connecting Avraham's promise of offspring as numerous as the stars and his vision of exile in the deep sleep and darkness as the sun set, and Yaakov's dream of a ladder connecting heaven and earth, the stars above and the grain below. The baker dreams of bread; the cupbearer dreams of grapes. Pharaoh dreams of grain and cows.

Yosef collects grain "as numerous as grains of sand."  The end of the dream was declared from the beginning, but dreams can become nightmares of exile.

Now the question: what does Yosef really want from his brothers when he toys with them on their journeys to Egypt?

Yosef takes a series of steps designed to give his brothers every opportunity to say more than they are GUILTY.   At each opportunity, they come closer, but even in Yosef's  accusation  that  they are spies, they miss exactly what he says:

"But  Joseph had recognized his brothers, although they did not recognize him.    Joseph remembered the dreams which he  had  about them, and said to them,  'You  are spies; you have come to look at the  undefended  parts of our land .'"

Then they said to him, "No, my lord, but your servants have come to buy food. We are all sons of one man; we are honest men, your servants are not spies." Yet he said to them, "No, but you have come to look at the undefended parts of our land!" But they said, " Your servants are twelve brothers in all , the sons of one man in the land of Canaan; and behold, the youngest is with our father today, and one is no longer alive." Joseph said to them,  (14) " It is as I said to you , you are spies;  by this you will be tested : by the life of Pharaoh, you shall not go from this place unless your youngest brother comes here! (Ge 42:8-15 NASB)

וַיֹּאמֶר  אֲלֵהֶם יֹוסֵף  הוּא אֲשֶׁר דִּבַּרְתִּי

" he  is what I spoke to you about"