1. A computer-readable, non-transitory medium storing therein an operation management support program causing a computer to execute a process, the process comprising: acquiring and storing into a storage unit, execution history information that indicates for each activity diagram, elements in a given order indicating a series of processing executed based on the activity diagram and indicates, among configuration items stored in a database, a read destination that is read during execution of the elements and a write destination that is written during execution of the elements, wherein the activity diagram expresses work procedures for operation processes executed by a system under operation management, and the database stores configuration items representing attribute information of configuration elements of the system; searching among unselected elements that have yet to be selected from among all of the elements, for a second element of which read destination and write destination coincide with those of the first element selected from among all of the elements including elements indicated by the execution history information of each activity diagram, wherein the searching performed by referring to the read destination and the write destination read/written during execution of each element indicated by the execution history information of each activity diagram stored in the storage unit; assigning an element name to the first element and the element name same as that of the first element to the second element retrieved at the searching and of which read destination and write destination coincide with those of the first element, wherein the element name is information for uniquely identifying a given element among synonymous elements; generating for each activity diagram, element strings listing element names of consecutive elements indicated by the execution history information of the activity diagram, based on a result of the assignment of the element name to each element indicated by the execution history information of the activity diagram at the assigning; and outputting the element strings of each activity diagram generated at the generating.