Jesus promises the people that whatever they ask the Father in Jesus’s name will be given unto them.

3 Nephi 27:28–29

28 And now I go unto the Father. And verily I say unto you, whatsoever things ye shall ask the Father in my name shall be given unto you.
29 Therefore, ask, and ye shall receive; knock, and it shall be opened unto you; for he that asketh, receiveth; and unto him that knocketh, it shall be opened.

Elder Richard G. Scott said:

“‘Ask, and ye shall receive’ (3 Nephi 27:29) does not assure that you will get what you want. It does guarantee that, if worthy, you will get what you need, as judged by a Father that loves you perfectly, who wants your eternal happiness even more than do you.”

(“Trust in the Lord,” Ensign, Nov. 1995, 17.)