Sumif functiion limits 1 column

Trying to consolidate data from by month sales to the data by quarter.

The revenue by month is in a separate workbook
First column is the customer
A B C D E
Customer Jan Feb Mar Apl
Wallm 5 5 5 5
Sears 10 1 5 5


Have been trying to use
=SUMIF('Revenue 08'!A1:F30,Sears, 'Revenue 08'!B1:D30)

but this will only return the amount in Jan it will not sum Jan, Feb and Mar together

Is there a way that I can index based on criteria in column A “customer name”
That I can sum the date on another workbook that has the customer name and data by month.

Seems like there should be an easy way to do this but I cannot seem to get there

Bob

thanks that what I needed