replace array name in vookup

I have 2 spreadsheets. Spreadsheet "B" has multiple arrays defined. I use a vlookup statement in spreadsheet "A" to extract values from arrays in Spreadsheet "B".

I have a vlookup as follows: =VLOOKUP(E70,'Quotes+Orders_Worksheet_2018.xlsx'!NWINTLAY120,3)

This Vlookup works fine, with or without spreadsheet B open.

However, I would like to be able to read new values into the vlookup in spreadsheet A from a cell in spreadsheet "A"

For example, in cell g70, I have a cell which contains the value SWINTLAY200

I would like to be able to generate a new vlookup that would say:

=VLOOKUP(E70,'Quotes+Orders_Worksheet_2018.xlsx'!SWINTLAY200,3)

I would appreciate any suggestions. I am trying to avoid using macros or VBA.