ikke den skarpeste kniv i skuffen

あまり賢くなく、機転が利かない / 頭の回転が鈍い / 知性や判断力に欠ける

English Meaning

not being sufficiently skilled or clever / not the sharpest knife in the drawer

Han er ikke den skarpeste kniv i skuffen, men han er meget venlig.

彼はあまり賢くないが、とても親切です。

He is not the sharpest knife in the drawer, but he is very kind.