Using shared datasource in a look up function

Basically I have 2 datasources in my report. One is embedded and other one is shared. In one of the columns of the report I want to write an expression which fetches the data from the dataset corresponding to the the shared datasource.

But I am getting an error saying "Report item expressions can only refer to fields within the same dataset....".

So my query is whether we can we use a dataset from a SHARED DATASOURCE in LookUp function in Report Builder 2.0?

Thanks.