The document describes a proposed method for sequential query expansion using a concept graph. The method involves two stages: 1) initially sorting concepts in each layer of the concept graph by predicted quality score, and 2) sequentially selecting concepts using a decision criterion that either continues with the current concept layer, moves to the next layer, or stops expansion. The goal is to optimize retrieval performance while minimizing the number of evaluated concepts. The method is intended to address challenges in efficiently exploring a large concept graph during query expansion.