I don't know if there's an easier option somewhere else in the software, but this information can be achieved by comparing your data files with your MaxDiff design file.
MaxDiff in Lighthouse Studio uses a design file, which details which items are shown in each task for every design ID. If you cross reference the design ID for respondents with this design file, you can determine how many times each item was shown to a respondent.
Note that if your MaxDiff uses a constructed list, the values in the design file will actually represent the positions of the items in the constructed list, not the positions of the items in the predefined list. You'll need to factor in the respondent's constructed list contents to "convert" from the values in the design file to the items in the predefined list.