OP has mentioned that 'search' is not a noun and hence can't be modeled as a resource. First of all, 'search' can be used as a noun in the sense of quest/query

OP has mentioned that 'search' is not a noun and hence can't be modeled as a resource. First of all, 'search' can be used as a noun in the sense of quest/query - 'His search for the Holy Grail was fruitful.' Secondly, we happen to have a multi-model search in our application and we treat it as a resource. This has worked out very well for us and our users can easily craft search queries just like for the rest of the RESTful resources.