retrieve only one value according to another value

hi there, i have thousands of data for me to look at.

its something like this. based on the sample attached file, in Sheet2, in the yellow highlighted cell, i need to display the value based on B1 from Sheet1.

in the file, i want to retrieve c34's value in col B. there are several c34 in col A but all the values belongs to 1 in col B. i want to be able to take in c34's col B value that is, 1 and not the sum.

i keep trying sumif formulae but it gives me a 0. any ideas?