Online word-of-mouth (WOM) has become an important reference for customers’ online purchase decisions. However, current studies ignore the various effects of WOM in different components, i.e., online reviews and the replies in the question and answer (Q &A) discussion area. To fill such a research gap, this study explores the relationship between WOM in two different forms and product sales. We measure the semantic features and thematic consistency of two forms of WOM and product sales. The findings show that the review component and Q&A component differ significantly in terms of quantity and content richness, with the review component being richer and more voluminous and the Q&A section having less content and relatively less quantity in comparison. Besides, the OLS results suggest that topic consistency has a negative impact on product sales, while the richness characteristics of both have a positive impact on product sales, and that the content richness of the Q&A component has a greater impact on sales than the review component
