"talk specifically" is a grammatically correct sentence and can be used in written English.
For example, you could write, "Please talk specifically about the challenges you faced during the project."
A. Let's talk specifically about terrorism.
Parcells has declined to talk specifically about Johnson's contract.
District officials declined to talk specifically about Sebastian's case.
Grossman didn't talk specifically about politics, or about the country's leaders.
Any candidate who can't talk specifically to these concerns is doomed.
These projects are impactful and have results". Wasserman declined to talk specifically about the president's budget.
But we can't talk specifically about it until sometime in January.
"I am aware that an MEP has asked to talk specifically about the forthcoming Referendum".
In an interview last Thursday, Ms. Masto declined to talk specifically about the case against L.P.S.
PRESIDENT OBAMA: Well, let me talk specifically about what I think we need to do.
It was also seen as a signal to Syria that Israel is willing to talk specifically about borders.
