My thoughts are in blue, words to delete are in red, suggested rephrasing is in orange.

Detective Sergeant Melanie Hunter is suffering through the posh fundraiser of her former best friend’s foundation when a Russian journalist, who seemingly knows too much about her past, approaches her. But we know nothing about her past, so this doesn't carry much of a punch. What does he approach her about? Why would it make her nervous? Before she can confront him, this wording feels odd, since he's presumably right in front of her Detective Chief Inspector Harry Williams unless Williams is going to recur again in the query, I wouldn't bother naming him calls her, asking her to a crime scene — an unidentified young woman found strangled in a park.

A well of contradictions from the get-go, Jane Doe’s case takes a dark turn for Melanie when a tattoo is found etched on the woman’s inner thigh. The sloppy initials scream human trafficking. Melanie sports matching ones on her ribcage. Soon, she finds herself sucked back into an insidious world hiding in plain sight. A world that turned her into a murderer. Oh, nice! Is this what the journalist was onto? A nod in the beginning would be good

When bodies start piling up, Melanie realizes this runs deeper than she’d ever imagined. Target on her back, she embarks on a journey across Romania and Russia to bring down the leader of a human trafficking ring and to prevent other girls from becoming the next Jane Doe. Her obsession for the truth is deadly. One wrong move will be the end of her. Still, she owes it to all those lost girls and to herself to try. This is a bit vague. There's a big bad guy, and she's got to bring him / it down, but that's the plot of pretty much all thrillers. What are the stakes? What's at risk, other than the obvious? Is she having psychological problems b/c of her own past? How does the fact that she murdered someone play into the plot? Why Russia? Is that where she's from? What's the connection?

THE LOST GIRLS is an adult thriller, which stands complete at 96,000 words, with series potential.

Born and raised in Romania, I currently live in a small town called Drobeta-Turnu Severin and I am simultaneously working towards obtaining an MBA and my second Bachelor’s Degree in Law. With my first novel, I wanted to showcase a vivid picture of life in poorer Eastern European countries and how they have come to be plagued by human trafficking.

Great bio. Really good to establish yourself as able to write this setting - but you need to clarify what the connection is to the plot within the query. Overall, this is well written and interesting, but we need those little details that are going to make this standout from every other thriller on the shelf.