lookup calculate value item, from the List loockup

have you checked documentation for lookup function?

http://help.nintex.com/en-US/nintex2013/help/#Forms/RootCategory/Designer/Nintex.Forms.LookupFunction.htm%3FTocPath%3DFo… 

Does your list title in the formula have 2 spaces between Budgets and Rubrica? The url shows two %20 which is a HTML code for a space.

yes, the name of list have space

I changed the list name because of the spaces and no longer gives the error of the page.
I can query the sharepoint (CALM), but it still does not return the value of the "Title" field.
The fields are correct and the search value is as well.

Formula: lookup("/finance|Budgets","Description",parseLookup(Rubrica),"Title")

[/finance|Budgets-0ba3c2bc-4f2b-47ac-ac16-b05cd35f6454] - Querying SharePoint for list item data: Query [<View><Query><Where><Eq><FieldRef Name='Description'  /><Value Type='Text'  >Standard cables Extrusion Line</Value></Eq></Where></Query><RowLimit>1000</RowLimit></View>]

Why don´t return nothing?

- does a user performing lookup has sufficient permissions to the other site and list?

- make sure you do not have any trailing spaces in names (site name, list name, field name ....), they are hard to spot

- try lookup for an item without spaces in description field

- try to convert your lookup as follows

lookup("/finance|Budgets","ID",parseLookup(Rubrica,false),"Title")

when put false, return to filter the ID.

I create new formula using trim because the spaces

lookup("/finance|Budgets","Description",trim(parseLookup(Rubrica)),"Title")

But don't works

filter I received:

[/finance|Budgets-19205d39-3d0d-4f6d-bafe-870e0ab27e35] - Querying SharePoint for list item data: Query [<View><Query><Where><Eq><FieldRef Name='Description'  /><Value Type='Text'  >saddasdsadsdasd</Value></Eq></Where></Query><RowLimit>1000</RowLimit></View>]

when put false, return to filter the ID.

yes, that's the point, to compare by unique ID and not by text. lookup by ID is much more reliable.

I would strongly recommend to make lookup by ID.

have you checked first two hints as well?

Yes I checked, i have permissions and not have any spaces.

Perfect it works
Thanks so much for your support