Here is a powerful dua for Salat Dhuha where you can increase your rizq. It is recited by Saad Al Qureshi. It is written in Arabic and English.

للّٰهُمَّ إِنَّ الضُّحَآءَ ضُحَآؤُكَ وَالْبَهَآءَ بَهَاؤُكَ وَالْجَمَالَ جَمَالُكَ وَالْقُوَّةَ قُوَّتُكَ وَالْقُدْرَةَ قُدْرَتُكَ وَالْعِصْمَةَ عِصْمَتُكَ اللّٰهُمَّ إِنْ كَانَ رِزْقِيْ فِي السَّمَآءِ فَأَنْزِلْهُ وَإِنْ كَانَ فِي اْلأَرْضِ فَأَخْرِجْهُ وَإِنْ كَانَ مُعَسِّرًا فَيَسِّرْهُ وَإِنْ كَانَ حَرَامًا فَطَهِّرْهُ وَإِنْ كَانَ بَعِيْدًا فَقَرِّبْهُ بِحَقِّ ضُحَآئِكَ وَبَهَائِكَ وَجَمَالِكَ وَقُوَّتِكَ وَقُدْرَتِكَ اٰتِنِي مَآ اٰتَيْتَ عِبَادَكَ الصَّالِحِيْنَ

Allahumma Innadh Dhuha-A Dhuha-Uk Wal Bahaa-A Bahaa-Uk. Wal Jamaala Jamaaluk. Wal Quwwata Quwatuk. Wal Qudrata Qudratuk. Wal Ishmata Ishmatuk Allahuma Inkaana Rizqi Fis Samma-I Fa Anzilh. Wan Inkaana Fil Ardhi Fa-Akhrijh. Wa Inkaana Mu’asiran Fayassirh. Wa Inkaana Haraaman Fathahhirh. Wa Inkaana Ba’idan Fa Qaribh Bihaqqiduhaa-Ika Wa Bahaaik Wa Jamaalika. Wa Quwwatika Wa Qudratik. Aatini Maa Ataita Min’Ibadikash Shalihin.

“Oh Allah, verily the time of Dhuha is but Your time of Dhuha, all beauty is but Your beauty, all strength is but Your strength, all power is but Your power and all protection is but Your protection.””Oh Allah, if my rizq is still in the the skies, please let if down and if it’s still in the ground, please let it out. Please make it easier if it is hard, if it is haraam please make it halal and please make it nearer if it is still far away. The blessings of the time of Dhuha, Your greatness, Your beauty, Your strength and Your power; bestow upon us all that you have bestowed unto Your righteous servants.”