A method and system for searching a graph in parallel which constructs an abstract representation of an AND/OR graph using state-space abstraction. The abstract representation of the graph includes one or more abstract nodes having duplicate detection scopes and one or more abstract edges having operator groups adjusted for AND node outcomes. The duplicate detection scopes of the abstract nodes are partitioned into smaller duplicate detection scopes using edge partitioning, wherein the abstract edges are used to define the smaller duplicate detection scopes. Nodes in the current search layer are expanded by a processing unit using the adjusted operator groups of outgoing abstract edges of the abstract nodes mapped into by the nodes, wherein the nodes expanded in parallel use adjusted operator groups associated with abstract edges having disjoint duplicate detection scopes. The method progresses to the next search layer once all the adjusted operator groups in the current search layer have been used for node expansions.