This is almost certainly a for Warhammer Fantasy Battles 8th edition , focusing on the Wood Elves (Elfes Sylvains). There is no official GW-published "Livre D'armée Elfes Sylvains V8" — the official 8th edition Wood Elves book was released in English in 2014, and French translations exist, but "V8" here suggests a homebrew or community revision.
It seems you’re looking for a of a document titled "Livre D'armée Elfes Sylvains V8 Pdf" — which appears to be French for "Army Book: Wood Elves V8 PDF" . Livre D 39-armee Elfes Sylvains V8 Pdf