The phrase "further signals" is correct and usable in written English.
You can use it to refer to additional signs, hints, or clues that have emerged, beyond what were already present. For example, "The recent drop in stock prices further signals a potential economic recession."
A new treaty with Armenia further signals how seriously Ankara means its "zero problem" good neighbor policy.
Just raising taxes further signals an unwillingness to grapple with the inefficiencies of the French state.
But drivers often reflect their ignorance of the law by blithely zipping by, sometimes prompting further signals by the frustrated equestrians.
"This is the most significant international deal in the history of Showtime, and further signals the value and prestige of its content brand in the global marketplace". said Armando Nunez, chief executive of CBS's global distribution group.
Wall Street will be looking for further signals about Chinese demand Tuesday, as export-dependent giants like 3M and DuPont report results and discuss their business outlook.
Low government-bond yields and falling commodity prices are further signals of poor economic momentum.Although there have been tentative signs that the euro-zone economy is recovering, the world has been very reliant on China and America in recent years.
Mr Fillon's rise sends a particularly resonant further signal.
A further signal came on Thursday from a government business spokeswoman in the Lords.
This investment is a further signal of our long term commitment to the UK, and to the northwest".
On Monday, Trump fired his campaign manager, Corey Lewandowski, a further signal of turbulence in Trump's effort to pivot towards the general election.
The sale of the plots after creditors threatened to come after his art-filled New York house came as a further signal of trouble.
