5. A computer-implemented method, comprising: receiving a threshold error distance; receiving a first search term and a second search term; querying an inverted token next valid character tree with the first search term and the second search term, wherein each branch through the tree defines a token and a document set for the token is stored at a leaf node; wherein each branch has an error distance which comprises the number of edit operations to transform the token associated with the branch to at least one of the search tokens; calculating a first document error list of error distances for the first search term and inverted token next valid character tree; calculating a second document error list of error distances for the second search term and the inverted token next valid character tree; comparing the first document error list and the second document error list to identify common document identifiers in both the first document error list and the second document list with a sum of error distances from the first and second document error list that is less than or equal to the threshold error distance; and providing a result set of the common document identifiers with the sum of error distances from the first and second document error list that is less than or equal to the threshold error distance.
6. The method of claim 5 , wherein the search tokens include at least one token prefix.