I watched Who rules the world recently and I absolutely love the female lead. She is smart,  understanding and strong. She didn't focus much on romance till later episodes and even then she prioritises other important things before romance. I would like a Cdrama with such a female lead who is no less stronger than any of the other characters and someone who doesn't fall in love at all. 

My recommendations:

The Message  - Smart FL, not much romance. 

Young Blood - Smart FL and ML form the perfect team. There's romance, but it's not the main focus.

Who Is the Murderer - No romance, FL is okayish smart, but the story is more focused on the ML.

 Nadia-Ruby:

you could try these - 

The Long Ballad 

The Song of Glory 

Rookie Agent Rouge 

Princess Agents 

Story of Yanxi Palace 

The Rise of Phoenixes  

There is some romance in many of those (not seen all), although it's quite subtle and minimal. But surely the main story line is not about the romance, although it is not the center focus it does affect the story.