Multiple vlookups in the same cell, with their values coming from different drop down lists. How do I get a blank when one of the dropdowns isnt used?

Question

Title pretty much says it all.

I have multiple dependent drop down lists (A2:H2)

Each time you select something, a corresponding number is entered into I2, with the numbers being separated by commas.

However, you MUST select a value from each drop down list or else you get #N/A error.

How can I make excel just "skip" or "ignore" missing values?

Thank you!

P.s.

I have already tried the IFERROR and IFNA commands but they do not work. I either get "TRUE" , with no numbers at all. And I also don't know how to make this work for about 6 different vlookups.

UPD:

=VLOOKUP(A8,'New Categories'!A$3:B19,2,FALSE) &", " &
 VLOOKUP(B8,'New Categories'!A$3:B206,2,FALSE) &", "&
 VLOOKUP(D8,'New Categories'!A$72:B$83,2,FALSE)&", "&
 VLOOKUP(E8,'New Categories'!$A$72:B$83,2,FALSE)&", "&
 VLOOKUP(F8,'New Categories'!$A$59:B$68,2,FALSE)&", "&
 VLOOKUP(G8,'New Categories'!$A$59:B$68,2,FALSE)&", "&
 VLOOKUP(H8,'New Categories'!$A$59:B$68,2,FALSE)

Answer 1

Use this one:

=IFERROR(VLOOKUP(A8,'New Categories'!A$3:B19,2,FALSE), "") &
 IFERROR(", " & VLOOKUP(B8,'New Categories'!A$3:B206,2,FALSE), "") &
 IFERROR(", " & VLOOKUP(D8,'New Categories'!A$72:B$83,2,FALSE), "") &
 IFERROR(", " & VLOOKUP(E8,'New Categories'!$A$72:B$83,2,FALSE), "") &
 IFERROR(", " & VLOOKUP(F8,'New Categories'!$A$59:B$68,2,FALSE), "") &
 IFERROR(", " & VLOOKUP(G8,'New Categories'!$A$59:B$68,2,FALSE), "") &
 IFERROR(", " & VLOOKUP(H8,'New Categories'!$A$59:B$68,2,FALSE),"")