In this process-based study, we introduced a collocation tool with a new interface and advanced search features and examined how a class of EFL college students interacted with it. To elicit their tool consultation behaviors, a vocabulary test with collocation questions was designed. The students' use of the tool to answer the vocabulary questions was screen-recorded for further analysis, serving as the major data source. One-on-one interviews with selected students were then conducted to clarify issues related to the study and their experience in using the tool. The findings indicated that the pattern-based tool was efficient in helping students solve collocation problems. This paper concludes with some pedagogical implications and suggestions for further research.