He is asking about a du’aa’ to bless his business
There is nothing in the Sunnah to indicate that it is mustahabb to say a particular dhikr or du’aa’ for help in business or earning a living, except that which was narrated from Umm Salamah, that the Prophet (peace and blessings of Allaah be upon him) used to say after Fajr prayer: “Allaahumma inni as’aluka rizqan tayyiban, wa ‘ilman naafi’an, wa ‘amalan mutaqabbalan (O Allaah, I ask you for good (halaal) provision, beneficial knowledge and accepted good deeds).”
Narrated by Ahmad in al-Musnad (6/294_ and Ibn Majaah in al-Sunan (66).
Al-Haythani said in Majma’ al-Zawaa’id (10/146): Its men are thiqaat (trustworthy). End quote. And it was classed as hasan by al-Haafiz ibn Hajar as it says in al-Futoohaat al-Rabbaaniyyah (3/70). It was classed as saheeh by al-Albaani in Saheeh Ibn Majaah.
As you can see, it is a du’aa’ that is general in meaning and includes earnings from business as well as from farming, employment or manufacturing. This is how the Sunnah is in du’aa’s that are concise in wording and comprehensive in meaning.
But it is mustahabb for you to ask Allaah for what you need by name, using whatever simple words and phrases Allaah enables you to say. So you may say for example: O Allaah, help me in my business, or O Allaah, bless me in my business, or O Allaah, make me independent of means so that I have no need of that which is haraam, or decree for me therein that which is good and makes me independent of means… and so on.
More important than the wording of the du’aa’ is sincerity in du’aa’, focusing properly and turning to Allaah fully, for Allaah does not look at the eloquence of the words, rather He looks at what is in the heart of sincerity, humility and longing for His mercy. From this you may know that saying du’aa’ in languages other than Arabic is also permissible, if the du’aa’ is general in meaning and was not narrated in specific words in the Qur’aan or Sunnah.
You should also note that fearing Allaah (taqwa) is a means to attain all success, and that the business by means of which a person seeks to attain the pleasure of Allaah and in which he pays heed to His command and prohibitions, is a business that will be blessed and helped, if Allaah wills, and that haraam things erase all blessings, as Allaah says (interpretation of the meaning):
“Allaah will destroy Riba and will give increase for Sadaqaat (deeds of charity, alms). And Allaah likes not the disbelievers, sinners”
And the Prophet (peace and blessings of Allaah be upon him) said: “Even if riba increases a thing, its consequences lead to loss.”
Narrated by Ahmad (1/395); classed as hasan by Ibn Hajar in Fath al-Baari (4/369); classed as saheeh by al-Albaani in Saheeh al-Jaami’ (3542).
Yahya ibn Mu’aadh al-Raazi (258 AH) – who was one of the best of the salaf –said:
Obedience will be stored in the stores of Allaah, and the key (to obedience) is du’aa’, and it becomes effective by means of halaal earnings.
Imam al-Ghazali (may Allaah have mercy on him) said, when discussing what should be paid attention to when doing business, in Ihya’ ‘Uloom al-Deen (2/103):
It us essential to have a good intention and sound belief when starting out in business, so a man should intend to make himself independent of means so that has no need of what is haraam and he does not need to ask of people or seek what they have, as halaal income makes him independent of others and help him to carry out his religious duties and sponsor his children, so that he will become like those who strive for the sake of Allaah. He should be sincere with the Muslims and love for all people what he loves for himself, and he should intend to follow the path of justice and good conduct in his dealings, and intend to enjoin what is good and forbid what is evil in everything that he sees in the marketplace. If he has all these sound beliefs and intentions in his heart, he will be striving in the path of the Hereafter. And if he earns money then this is something extra, and if he loses in this world he will prosper in the Hereafter. End quote.
And Allaah knows best.