"Agua" is a common title for Spanish-language works. A notable recent "Agua" related book is Agua: A Novel by Begoña Oro, or various scientific papers on water management.
There is an author by this name who often writes in the Romance or Young Adult genres. Agua - Alex Roma.epub
It is possible this is a niche indie release, a local academic paper, or a very recent work that hasn't been indexed by major databases yet. Potential Matches or Similar Titles "Agua" is a common title for Spanish-language works
The or general plot (e.g., sci-fi, romance, non-fiction)? a local academic paper