windows 10 – How to use External MIC with Laptop Speakers ON on Lenovo L340 Laptop?

I have Lenovo L340 laptop, it has one combo jack for audio & mic. I got one converter has one female combo port at one end and on the other side two males one for mic and one for audio.

I want to use external mic with my laptop speakers ON. But when I connect this combo jack to laptop, my laptop speakers are going OFF. How do I do that?

Thank you in advance.