These can be narrowing, like enforcing an atom or bond to be part of an aromatic ring, require an atom to exactly carry two hydrogen atoms or a positive charge. Or they may be broadening, allowing an atom to be either an oxygen or any halogen, or a bond to be a single or a double bond. Our substructure search method comes with the limitation that the query structure must not consist of multiple disjoint substructures, it is however possible to employ so called bridged bonds (corresponding to arbitrary paths of specific length) to connect disjoint substructures. It is noteworthy, that in comparison to most other methods, there are no limitations on the combinatorial library itself, e.g. any kinds of bond formation, ring closures or macrocyle formation that can be represented in a suitable way is supported.