diff --git a/service/soap/src/repository/BookRepository.java b/service/soap/src/repository/BookRepository.java
index 6649ddeb1ccda3a459fd57a1bae95c5e7eceadb0..669818eb376622cc6f638dca2b5c1f69d26521a0 100644
--- a/service/soap/src/repository/BookRepository.java
+++ b/service/soap/src/repository/BookRepository.java
@@ -168,7 +168,7 @@ public class BookRepository {
         DaftarPenjualan answer = new DaftarPenjualan(STRING_UNDEFINED, STRING_UNDEFINED, -1, 0);
 
         try {
-            String query = "SELECT id_buku, SUM(jumlah) AS jumlah FROM daftar_penjualan WHERE LOWER(kategori) LIKE LOWER(\"" + category + "\") GROUP BY id_buku ORDER BY SUM(jumlah) DESC LIMIT 1;";
+            String query = "SELECT id_buku, SUM(jumlah) AS jumlah FROM daftar_penjualan WHERE LOWER(kategori) LIKE LOWER(\"%" + category + "%\") GROUP BY id_buku ORDER BY SUM(jumlah) DESC LIMIT 1;";
             ResultSet rs = st.executeQuery(query);
             while (rs.next()) {
                 answer.setId_buku(rs.getString("id_buku"));