Please review following formula,

=IF(AD2="B10x5x5",VLOOKUP(AP2,B10X5X5,2),IF(AD2="B 10x10x5",
VLOOKUP(AP2,B10X10X5,2),"Your Choice"))

Depends on cell AD2, if is "B10x5x5" then Vlookup use table B10X5X5, or if
AD2 = "B10X10X5" then Vlookup use table "B10X10X5"

Then I trying to figure out a more general formula so I can have more table
to choose from, by using AD2 as a table Reference cell, but none of my trying
work, I Use Trim(AD2), TEXT(AD2,"##########"), proper(AD2)...

Is anyone have similar experience and can help me on this?

Thank a lot

and rewrite formula as