US retail goliath Sears, Roebuck and Co on Thursday posted a sharp rise in second quarter net profit as it was boosted by the sale of previously charged-off credit card accounts. The Illinois-based operator of 870 stores reported net income of $309 million, or $1.04 per share, for the quarter ended June 28, compared with net income of $229m, or 71 cents per share, in the year-ago period.