How Did The Jews Make Bricks Without Straw?

They didn't!! The point was that they had to go out & gather their own straw, instead of having it provided for them each day. However, the daily brick-making requirement was not lessened.

From Exodus 5.... (KJV 1611, public domain)
6. And Pharaoh commanded the same day the taskmasters of the people, and their officers, saying,
7. Ye shall no more give the people straw to make brick, as heretofore: Let them go and gather straw for themselves.
8. And the tale of the bricks, which they did make heretofore, ye shall lay upon them; ye shall not diminish ought thereof: For they be idle; therefore they cry, saying, Let us go and sacrifice to our God.
9. Let there more work be laid upon the men, that they may labour therein; and let them not regard vain words.
10. And the taskmasters of the people went out, and their officers, and they spake to the people, saying, Thus saith Pharaoh, I will not give you straw.
11. Go ye, get you straw where ye can find it: Yet not ought of your work shall be diminished.
12. So the people were scattered abroad throughout all the land of Egypt to gather stubble instead of straw.
13. And the taskmasters hasted them, saying, Fulfil your works, your daily tasks, as when there was straw.
14. And the officers of the children of Israel, which Pharaoh's taskmasters had set over them, were beaten, and demanded, Wherefore have ye not fulfilled your task in making brick both yesterday and to day, as heretofore?
15. Then the officers of the children of Israel came and cried unto Pharaoh, saying, Wherefore dealest thou thus with thy servants?
16. There is no straw given unto thy servants, and they say to us, Make brick: And, behold, thy servants are beaten; but the fault is in thine own people.
17. But he said, Ye are idle, ye are idle: Therefore ye say, Let us go and do sacrifice to the LORD.
18. Go therefore now, and work; for there shall no straw be given you, yet shall ye deliver the tale of bricks.