Here we have another example where the original text has the singular pronoun thou instead of the expected plural ye (or you). Note that the following appositive “many of you” uses the plural pronoun you. The pronoun thou is often used in the original text as a marker of the biblical style rather than as a strictly singular pronoun, and the critical text will restore such examples despite their nonstandard character. For earlier examples in the text, see 1 Nephi 3:29 and 1 Nephi 7:8. Also see the discussion under thou in volume 3.
Summary: Restore the singular “thou hast searched much / many of you”, the reading of the original text in 2 Nephi 9:4.