Sparse Value-Flow Analysis (SVFA) is essential for detecting software bugs such as null pointer dereference and memory leak. However, SVFA heavily relies on path-sensitive pointer analysis, which faces significant scalability challenges when analyzing industrial-scale projects, notably the summary-explosion problem. To address this issue, we propose \textsc{Hermes}, which symbolizes memory side effects and constructs an incomplete Sparse Value-Flow Graph (SVFG) called Lazy Symbolic Expression Graph (LSEG). Leveraging this structure, \textsc{Hermes} builds inter-procedural value flows relevant to bug detection only when necessary, significantly reducing the overhead of pointer analysis and streamlining the bug-search paths. Evaluations on large-scale real-world projects demonstrate that, compared to the state-of-the-art, \textsc{Hermes} achieves average speedups of at least 9.84$\times$ and 4.79$\times$ for pointer analysis and bug search, respectively, without sacrificing the effectiveness of bug detection.