Maker of heaven and earth is one of several names of God that declare that He created the universe and everything in it, animate and inanimate. In the Jewish worldview the universe was divided into two parts, heaven and earth. The word heaven, shamayim, is a plural form, which might reflect the fact that they thought of heaven as having three levels: atmosphere, space, and the abode of God.
The word ‘asah, from which ‘oseh derives, means, “to do, to make or to fashion.” It is broader in scope than the word bara’ that is normally translated as “Creator.”
Maker of heaven and earth in Hebrew:
‘Oseh shamayim wa’arets
Strong’s Concordance numbers: 6213a, 8064, 776
Bible reference: Ps. 115:15
May you be blessed by the Lord,
the Maker of heaven and earth. (Psalm 115:15)
Similar names for God are: Maker of all, Lord of heaven and earth, and Possessor of heaven and earth (which the Message Bible has as Possessor and Maker of heaven and earth, and the KJV has as Creator of heaven and earth).