but also the extent to which the labeling or advertising fails to reveal facts material in the light of such representations or material with respect to consequences which may result from the use of the article to which the labeling or advertising relates under the conditions of use prescribed in the labeling or advertising thereof or under such conditions of use as are customary or usual.

翻译为:

但是，在标签和广告材料中也没有说明有关按照标签和广告所介

绍的该商品（产品）使用方法,或者按照通常习惯使用方法使用该

产品后可能产生的实际后果的资料。

（理解分析：
主导词是：the extent，“to which the labeling or advertising fails to reveal facts material”是the extent的定语，即说明标签和广告没有达到包涵……的程度.
in the light of 意为“按照，依据”， with respect to意为“有关，关于”.这两个词组在定语从句中做状语。Consequences 是with respect to的宾语，which may result from the use of the article 是 Consequences定语从句。to which the labeling or advertising relates 又是上定语从句中article 的定语从句，因为relates 后接to，所以：to which. Under ……or under ……都是最后一个定语中的条件状语.）