1. A method for dynamic two-way auction, applicable for auctioning participating goods, comprising: (1) setting, by a server, descriptive information, possible search conditions, and relations which associate each search condition with the descriptive information of all participating goods, wherein the setting of descriptive information of participating goods comprises a step of price standardization, wherein the descriptive information, possible search conditions, and relations which associate each search condition are set up and stored on the server; (2) sending, by a buyer terminal and/or a seller terminal, a search request which includes a search condition to the server; (3) parsing, by the server, the search request to obtain the search condition, determining whether a definition of a relation which associates the search condition with the descriptive information has been recorded, and performing step (4) responsive to a determination that the definition of a relation has not been recorded; (4) defining, by the server, a relation which associates the search condition with the descriptive information of some participating goods, wherein the relation which associates the search condition with the descriptive information is defined by utilizing formal language and formal logic; and (5) searching, by the server, for all participating goods which satisfy the search condition according to the relation which associates the search condition with the descriptive information, sorting the participating goods which satisfy the search condition according to bidding prices of buyers and offering prices of sellers to create a resultant auction queue, and informing the buyer terminal and/or the seller terminal of the resultant auction queue.