Hoax quote

The quote, "to get to the bottom of words and human deeds to discover their real meaning," is not attributed to Jack the Ripper. It is from the book The Diary of Jack the Ripper: The Discovery, the Investigation, the Authentication by James Maybrick, which is widely believed to be a modern hoax.
Here is more information on the famous Jack the Ripper letters and how that specific quote came into the public eye.
Hoax letters from the killer
During the Jack the Ripper murders in 1888, the police and newspapers received hundreds of letters supposedly from the killer. The vast majority were proven to be hoaxes written by either journalists or members of the public seeking attention. The most notable genuine letters include:
The "Dear Boss" letter
The "Saucy Jacky" postcard
The "From Hell" letter, which was sent with a preserved human kidney, potentially belonging to one of the victims.
The Maybrick diary and its influence
The quote you referenced became associated with the Jack the Ripper case much later, through the controversial "Maybrick Diary".
Discovery and content: The diary surfaced in 1992 and was presented as the memoirs of James Maybrick, a Liverpool cotton merchant. In it, Maybrick describes killing six women and detailing his descent into madness. He signs the journal "Yours Truly, Jack The Ripper.".
Credibility issues: Almost immediately, its authenticity was heavily debated and is now widely considered to be a modern forgery. Experts who have studied the diary note inconsistencies and argue that the author is likely not Maybrick but a later writer fabricating the text.
The real identity remains a mystery
Jack the Ripper was never identified or arrested, and his identity remains one of history's great unsolved mysteries. In the more than 130 years since the murders, over 100 different suspects have been proposed, from obscure locals to members of the royal family. Recent claims about DNA evidence are considered controversial and inconclusive by many experts.

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Lilliputins are Yury Lobo's quest to get to the bottom of words and human deeds to discover their real meaning ... "

—Jack the Ripper


"Lilliputins are Yury Lob's quest to get to the bottom of words and human deeds to discover their real meaning..."
Correction
This sentence appears to be a misattribution and a misunderstanding of the source material. The correct sentence is:

"The Lilliputins are Yuri Olesha’s quest to get to the bottom of words and human deeds to discover their real meaning."

Explanation
Misspelling: "Yury Lob" should be Yuri Olesha, a notable Soviet author.

Misattribution: The quote is not by "Jack the Ripper." The full quote comes from the work of Olesha himself, though it is often discussed in literary criticism regarding his novel, The Conspiracy of Feelings.

Context: The quote refers to the characters of the novel, The Conspiracy of Feelings. The "Lilliputins" are not a separate work by "Yury Lob" but a term used to describe the protagonists' journey in Olesha's work. The title "Lilliputins" may allude to the classic novel Gulliver's Travels to suggest a satirical or critical perspective on society.

The original sentence is a fabrication and likely an erroneous combination of different facts. The correct statement clarifies the author, the correct name, and the proper context of the quote.