Comparative evidence

sekh₁, sekh₂, sekh₃

• Hitt. sākk- /sakk-, sekk- 'know' (about), 'be aware', 'experience', 'heed', 'pay attention', 'recognize', 'remember', 'be expert' (in), 'be acquainted' (CHD S: 21ff., EDHIL: 695ff.)

References

EDHIL = Kloekhorst, A. 2008. Etymological Dictionary of the Hittite Inherited Lexicon. Brill.
CHD = Güterbock H.G., H.A. Hoffner, Th.P.J. van den Hout (eds.), 1980 - . The Hittite Dictionary of the Oriental Institute of the University of Chicago. Chicago.