Bosom wasn't used in TEoTW. In TGH and TDR together it was used eleven times. As far as The Gathering Storm, bosom is used three times (never just trust Ideal Seek) and it appears that in the Chapter we have of ToM it is already been used three times (must be because they were trolling forums where people were complaining about word usage and wanted to appease the fans) and not sure in the prologue, haven't gone breast/bosom hunting there...yet!

Additionally, breasts is used four times in TGS, although Brandon seems to have only used the typical "beneath her breasts" variation, instead of adding a "under her breasts" and "below her breasts" or even throwing out a "between her breasts" which happens to be a favorite of mine (although Fires of Heaven does use quite a lot "beneath her breasts" and Path of Daggers is almost explicitly "beneath her breasts", although I do quite like the inclusion of "slopes" regarding breasts that showed up in a few books)...but I'll be honest, while reading the low breast count I knew it was definitely a Mormon author, because I know the books that damn well and I know for sure Jordan was on the upswing of breast and bosom usage before he died. I hope Brandon increased the breasts in ToM (as it already seems apparent we are getting more bosom.)