need help, i want to collect data from 2 detail tables and 1 master table

[Hendy Hendrawan]

SELECT master_persediaan.kode_barang, master_persediaan.nama_barang, master_persediaan.satuan, master_persediaan.stok_barang, sum( detail_pembelian.jumlah ) AS 'Masuk'
FROM master_persediaan
LEFT JOIN detail_pembelian ON detail_pembelian.kode_barang = master_persediaan.kode_barang
GROUP BY master_persediaan.kode_barang
ORDER BY master_persediaan.kode_barang ASC

kode_barang | nama_barang | satuan| stok_barang| Masuk
BRG0001 | Pasir| Box | 50 | 202
BRG0002 | Paku Kg | 100 | 240
BRG0003 | Cat | Kaleng| 10| 123
BRG0004 | Baut | Biji | 20 | NULL

then
SELECT master_persediaan.kode_barang, master_persediaan.nama_barang, master_persediaan.satuan, master_persediaan.stok_barang, sum( detail_retur_pmb.jumlah_barang ) AS 'Retur'
FROM master_persediaan
LEFT JOIN detail_retur_pmb ON detail_retur_pmb.kode_barang = master_persediaan.kode_barang
GROUP BY master_persediaan.kode_barang
ORDER BY master_persediaan.kode_barang ASC

kode_barang |nama_barang |satuan |stok_barang | Retur
BRG0001 |Pasir |Box |50 | 6
BRG0002 |Paku |Kg |100 | 50
BRG0003 |Cat |Kaleng |10 | 2
BRG0004 |Baut |Biji |20 | NULL

i need query to get this result :
kode_barang |nama_barang |satuan |stok_barang |masuk Retur
BRG0001 |Pasir |Box |50 |202 |6
BRG0002 |Paku |Kg |100 |240 |50
BRG0003 |Cat |Kaleng | 10 | 123 |2
BRG0004 |Baut |Biji |20 |NULL |NULL