The supplication the Prophet (peace and blessings be upon him) taught Buraydah (may Allah be pleased with him)

It is narrated from Sayyiduna Buraydah al-Aslami (may Allah be pleased with him) that he said: The Messenger of Allah (peace and blessings be upon him) said to me: "Say: 'Allahumma inni da'ifun fa qawwi fi ridaka da'fi, wa khudh ilal-khayri bi-nasiyati, waj'alil-islama muntaha rida'i. Allahumma inni da'ifun fa qawwini, wa inni dhalilun fa a'izzani, wa inni faqirun farzuqni' (O Allah, I am weak, so turn my weakness into strength in attaining Your pleasure; take me by my forelock towards good, and make Islam the utmost of my pleasure and joy. O Allah, I am weak, so give me strength; I am lowly, so grant me honour; and I am poor, so grant me provision)."
The chain of this hadith is sahih (authentic), but the two Shaykhs (Bukhari and Muslim) did not record it.

It is narrated from Sayyiduna Thawban (may Allah be pleased with him) (the freed slave of the Messenger of Allah (peace and blessings be upon him)) that the Messenger of Allah (peace and blessings be upon him) said: "It was said to me: O Muhammad! Speak, and you will be heard; ask, and you will be given." He (peace and blessings be upon him) said: "So I said: 'Allahumma inni as'aluka fi'lal-khayrat, wa tarkal-munkarat, wa hubbal-masakin, wa an taghfira li wa tarhamani, wa idha aradta bi-qawmin fitnatan fa tawaffani ilayka wa ana ghayru maftun. Allahumma inni as'aluka hubbak, wa hubba man yuhibbuk, wa hubban yuballighuni hubbak' (O Allah, I ask You for the doing of good deeds, the abandoning of evils and love of the poor, and that You forgive me and have mercy on me; and when You intend to put a people to trial, take me to Yourself without my falling into the trial. O Allah, I ask You for Your love, the love of whoever loves You, and a love that will bring me to Your love)."
This hadith is sahih (authentic) on the condition of Imam Bukhari, but the two Shaykhs (Bukhari and Muslim) did not record it.