Systems and methods for system event searching based on heterogeneous logs are provided. A system can include a processor device operatively coupled to a memory device wherein the processor device is configured to mine a variety of log patterns from various of heterogeneous logs to obtain known-event log patterns and unknown-event log patterns, as well as to build a weighted vector representation of the log patterns. The processor device is also configured to evaluate a similarity between the vector representation of the unknown-event and known-event log patterns, identify a known event that is most similar to an unknown event to troubleshoot system faults based on past actions for similar events to improve an operation of a computer system.