To multiply these two terms you multiply each individual term in the left parenthesis by each individual term in the right parenthesis.
#(color(red)(sqrt(3)) + color(red)(sqrt(2)))(color(blue)(sqrt(4)) + color(blue)(2sqrt(2))) =>#
#(color(red)(sqrt(3)) + color(red)(sqrt(2)))(color(blue)(2) + color(blue)(2sqrt(2))) =>#becomes:
#(color(red)(sqrt(3)) xx color(blue)(2)) + (color(red)(sqrt(3)) xx color(blue)(2sqrt(2))) + (color(red)(sqrt(2)) xx color(blue)(2)) + (color(red)(sqrt(2)) xx color(blue)(2sqrt(2)))#
#2sqrt(3) + 2sqrt(3)sqrt(2) + 2sqrt(2) + 2sqrt(2)sqrt(2) =>#
#2sqrt(3) + 2sqrt(3 * 2) + 2sqrt(2) + 2sqrt(2 * 2) =>#
#2sqrt(3) + 2sqrt(6) + 2sqrt(2) + 2sqrt(4) =>#
#2sqrt(3) + 2sqrt(6) + 2sqrt(2) + (2 * 2) =>#
#2sqrt(3) + 2sqrt(6) + 2sqrt(2) + 4#
If necessary, we can now factor out like terms:
#2(sqrt(3) + sqrt(6) + sqrt(2)) + 4 =>#
#2(sqrt(6) + sqrt(3) + sqrt(2)) + 4 =>#