In this paper, a study based on data mining techniques in order to extract knowledge in a data set with information about users history associated to an e-commerce website is presented. These data are collected from the e-commerce website OrOliveSur.com which is related to the sell of extra virgin olive oil and iberian products from Spain. The main purpose is to apply a set of descriptive data mining techniques to obtain rules that allow to help to the webmaster team to improve the design of the website. Techniques used are clustering, association rules and subgroup discovery. Therefore, in this web usage mining study can be analysed different knowledge with respect to these techniques used, i.e. we present a variety of groups and/or rules associated for each technique