Authentic Supplication Number 135.

'Abi Hurayrata  reported that the Prophet  said: The bondservant shall continue to have his supplications answered so long as he does not supplicate for sin, or the severance of kinship; so long as he does not rush it. They said: O Messenger of Allah  what is "rushing it?" He said [that] he say I have supplicated, and supplicated, and I have not seen an answer; thereupon, getting tired and abandoning supplication.

Al-`Adawee said it was sound and that it was reported by Muslim, page 52 of volume 17; At-Tirmidhi on page 470 of volume 11 of Tuhfah. He said that At-Tirmidhi said that it was a strange hadeeth.