I am making an assumption that you have two Excel files with multiple sheets and that there are 'keys' on each sheet to tie your data together. Without sample data, we are just guessing. If your question is how to loop through the excel spreadsheets then it can be accomplished pretty easily. Take for example the following two Excel files,
Notice the file names. Same name except for the 3 and 4.
Each files has multiple sheets and each sheet has the same data fields. You can do something like the following to load the data from sheet1 from both files.
(ooxml, embedded labels, table is Sheet1);
Since the file names are similar, you can use an * in the file name and Qlik will process all files in the specified directory based on the wildcard.
This same process can be used for each sheet in the workbook.
Hope this is what you were looking for.