ESV: My son, beware of anything beyond these. Of making many books there is no end, and much study is a weariness of the flesh.
NIV: Be warned, my son, of anything in addition to them. Of making many books there is no end, and much study wearies the body.
NASB: But beyond this, my son, be warned: the writing of many books is endless, and excessive study is wearying to the body.
CSB: But beyond these, my son, be warned: there is no end to the making of many books, and much study wearies the body.
NLT: But, my child, let me give you some further advice: Be careful, for writing books is endless, and much study wears you out.
KJV: And further, by these, my son, be admonished: of making many books there is no end; and much study is a weariness of the flesh.
NKJV: And further, my son, be admonished by these. Of making many books there is no end, and much study is wearisome to the flesh.