Recommend a chinese drama

• I Hear Your Voice - When she was a kid, the FL witnessed the ML's father's murder. She testifies and the murderer is convicted. As an adult, the FL becomes a defence attorney. The ML is in high school and helps the FL deal with some cases, some of which involve murders. The ML and FL also help each other after the ML's father's murderer is released from prison. 
• The Untamed - One ML (WY) meets the other ML (LZ) when he visits LZ's sect to attend lessons along with other young cultivators. They investigate a supernatural death together shortly after meeting. Lots of other things happen (a civil war, for example) but there are a few more instances where you could say that the MLs are investigating murders. Most of the second half of the drama (when the leads are no longer students) is essentially one big murder investigation.
• Bring It On, Ghost - The ML is a college student who can see ghosts. The FL was a high school student and has been a ghost for five years. The FL helps the  ML deal with ghosts to make money. Some of those ghosts are murder victims. 

 emeraldarrows:

Maybe The Great Shaman Ga Doo Shim? The leads are students who are trying to solve the events happening around their school that involve ghosts.

Thank you... I've already watched this drama 😊

You might like to try Inference Notes. The leads are students and they solve mysteries.

Thank you for the recommendation.  

Luoyang

This is another excellent adaptation of a Ma Boyong’s novel, after The Longest Day in Chang’an. The main story is about three persons put together by faith to discover the conspiracy hatched against the rule of Emperor Wu Zetian (the only female emperor in the history of China) before it’s too late. This is a fast paced costume mystery thriller with good action sequences starring Huang Xuan, Victoria Song, Wang Yibo and Song Yi. I would say Victoria Song gave one of her best performance as an actress in this drama. I’m slightly disappointd with the ending but overall it’s a very good drama with excellent set, excellent cinematography, good plot lines, a story full of twists and turns that do not feel forced and good acting all round.