The book of Sirach was one of several books questioned during the Reformation and by a few early Christians (but was overwhelmingly considered canonical and quoted). Protestantism in its current forms today, especially among Evangelicals, rejects the book completely as Holy Scripture. The common criticism of the book was not it was not written in Hebrew, but just Greek, Latin and other languages. However, thanks in part of archaeology, the Dead Sea Scrolls among other discoveries, large parts of Sirach are being recovered in Hebrew text! This certainly had to be the case since Sirach is quoted several times in the Talmuds as Scripture–although it was eventually excluded from the Pharisaic canon (as were almost Ezekiel, Ecclesiastes, Lamentations, Songs of Solomon).
A link to the verses found in manuscripts. at present whole chapters are missing still, but several chapters have been found.