10. A non-transitory, computer-readable storage medium encoded with instructions executable by a processor to: in response to a query that provides keywords, use one or more web search engines to identify highly ranked web pages related to the keywords and highly ranked ontologies related to the keywords; extract semantics that are related to the keywords from the highly ranked web pages; combine the highly ranked ontologies and the extracted semantics to form an integrated ontology; identify relationships that are related to the keywords from the integrated ontology, the identify relationships comprising: from the integrated ontology, add one or more formulas that each includes at least one of the keywords as candidate formulas to a candidate pool, and perform an iterative process, comprising: record any candidate formula that includes all of the keywords as one of the relationships and remove the recorded candidate formula from the candidate pool, for each candidate formula in the candidate pool, determine one or more formulas from the integrated ontology that are relevant to the candidate formula, for each relevant formula, determine an implicit formula implied from the relevant formula and a corresponding candidate formula, and repeat the iterative process; and rank the identified relationships.
10. A non-transitory, computer-readable storage medium encoded with instructions executable by a processor to: in response to a query that provides keywords, use one or more web search engines to identify highly ranked web pages related to the keywords and highly ranked ontologies related to the keywords; extract semantics that are related to the keywords from the highly ranked web pages; combine the highly ranked ontologies and the extracted semantics to form an integrated ontology; identify relationships that are related to the keywords from the integrated ontology, the identify relationships comprising: from the integrated ontology, add one or more formulas that each includes at least one of the keywords as candidate formulas to a candidate pool, and perform an iterative process, comprising: record any candidate formula that includes all of the keywords as one of the relationships and remove the recorded candidate formula from the candidate pool, for each candidate formula in the candidate pool, determine one or more formulas from the integrated ontology that are relevant to the candidate formula, for each relevant formula, determine an implicit formula implied from the relevant formula and a corresponding candidate formula, and repeat the iterative process; and rank the identified relationships. 11. The non-transitory, computer-readable storage medium of claim 10 , wherein the instructions to rank the identified relationships include instructions executable by the processor to: determine a weight of any formula extracted from a highly ranked web page or originally located in a highly ranked ontology based on an order of the highly ranked web page or the highly ranked ontology provided by the one or more web search engines; determine a weight of any implicit formula that is implied from two or more formulas based on weights of the two or more formulas and a number of iterations that generated the implicit formula; and rank the identified relationships by weight.