Where does “ख्या” come from?

ख्या (Sanskrit) comes from Proto-Indo-European kʷeḱ- — to see; to look.

Ancestry of “ख्या”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	kʷeḱ-	to see; to look

ख्या — Etymology, Origin & Word History | Etymology Explorer