PurposeThis study aims to explore the characteristics of collaborative information searching by comparing the differences in search experience and interaction between collaborative search mode and individual search mode and by analyzing the communication content and patterns during collaborative searches.Design/methodology/approachA user experiment was conducted using the Conference and Labs of the Evaluation Forum (CLEF)-Social Book Search platform, recruiting 16 individual and 18 collaborative participants. Each of the participants was required to complete two types of book search tasks in a lab setting. Interactions with the system were logged, and participants' experiences were captured through pre/post-search questionnaires. Additionally, the communication among collaborative participants was recorded and coded.FindingsThis study identified characteristics of collaborative information searching in three aspects. (1) Search experience: collaborative searchers showed a higher appreciation for the system’s functionality and aesthetics and were more engaged than individual searchers, despite experiencing slightly more mental strain. (2) Search strategies: in focus tasks, collaborative searchers made more decisions than individual searchers, indicating a need for book sorting. In open tasks, collaborative searchers take longer before making decisions, likely due to a higher level of interest and participation. (3) Communication content and pattern: collaborative searchers mainly discussed understanding and judgment of books and task plan. Searchers with same cognitive style talked more about search operations than those with different cognitive styles, while less about book judgment. Three communication patterns were identified: understanding-judgment, judgment-dominant and balanced. Judgment-dominant participants generally reported higher satisfaction with their search results than those in the other two patterns.Originality/valueThis study enhances understanding of collaborative search by comparing it with individual search and analyzing communication content, potentially inspiring collaborative search system and experiment design. Additionally, the coding table for communication between collaborative searchers offers valuable insights for future research.