diff --git a/src/main/java/com/trolley/trolley/InvoiceGateway.java b/src/main/java/com/trolley/trolley/InvoiceGateway.java
index 7fd42cc..b4fb26a 100644
--- a/src/main/java/com/trolley/trolley/InvoiceGateway.java
+++ b/src/main/java/com/trolley/trolley/InvoiceGateway.java
@@ -125,8 +125,8 @@ public Invoice fetch(final String invoiceId) throws Exception {
      * These options correspond to our documentation.
      * @param searchBy Enum of type Invoice.SearchBy denoting which field you want to search by
      * @param paramsList {@code List<String>} Required if 'searchBy' is either of these: 'invoiceId'
-     * 'recipientId', 'invoiceNumber', 'tags'. Set to 'null' otherwise.
-     * @param param String Required if 'searchBy' is either 'invoiceDate' or 'externalId'. Set to null otherwise.
+     * 'recipientId', 'invoiceNumber', 'tags', or 'externalId'. Set to 'null' otherwise.
+     * @param param String Required if 'searchBy' is 'invoiceDate'. Set to null otherwise.
      * @return {@code List<Invoice>}
      * @throws Exception
      */
@@ -141,11 +141,12 @@ public List<Invoice> search(final SearchBy searchBy,
             case INVOICE_ID:
             case RECIPIENT_ID:
             case INVOICE_NUMBER:
+            case EXTERNAL_ID:
             case TAGS:
                 if(null == paramsList){
                     throw new InvalidFieldException("variable paramsList can not be null for the provided searchBy parameter. Refer to method's Javadoc for more details.");
                 }
-                body = "{\""+searchBy.name()+"\":"
+                body = "{\""+searchBy.getKey()+"\":"
                     +new ObjectMapper()
                         .setSerializationInclusion(Include.NON_EMPTY)
                         .writeValueAsString(paramsList)
@@ -153,11 +154,10 @@ public List<Invoice> search(final SearchBy searchBy,
                 break;
 
             case INVOICE_DATE:
-            case EXTERNAL_ID:
                 if(null == param){
                     throw new InvalidFieldException("variable param can not be null for the provided searchBy parameter. Refer to method's Javadoc for more details.");
                 }
-                body = "{\""+searchBy.name()+"\":\""+param+"\"}";
+                body = "{\""+searchBy.getKey()+"\":\""+param+"\"}";
                 break;
         }
         final String endPoint = "/v1/invoices/search/";
@@ -176,8 +176,8 @@ public List<Invoice> search(final SearchBy searchBy,
      * These options correspond to our documentation.
      * @param searchBy Enum of type Invoice.SearchBy denoting which field you want to search by
      * @param paramsList {@code List<String>} Required if 'searchBy' is either of these: 'invoiceId'
-     * 'recipientId', 'invoiceNumber', 'tags'. Set to 'null' otherwise.
-     * @param param String Required if 'searchBy' is either 'invoiceDate' or 'externalId'. Set to null otherwise.
+     * 'recipientId', 'invoiceNumber', 'tags', or 'externalId'. Set to 'null' otherwise.
+     * @param param String Required if 'searchBy' is 'invoiceDate'. Set to null otherwise.
      * @return Invoices object that contains {@code List<Invoice>} that you can traverse through, and a Meta object with pagination information
      * @throws Exception
      */
@@ -198,7 +198,7 @@ public Invoices search(final SearchBy searchBy,
              if(null == paramsList){
                  throw new InvalidFieldException("variable paramsList can not be null for the provided searchBy parameter. Refer to method's Javadoc for more details.");
              }
-             body = "{\""+searchBy.name()+"\":"
+             body = "{\""+searchBy.getKey()+"\":"
                  +new ObjectMapper()
                     .setSerializationInclusion(Include.NON_EMPTY)
                     .writeValueAsString(paramsList)
@@ -212,7 +212,7 @@ public Invoices search(final SearchBy searchBy,
              if(null == param){
                  throw new InvalidFieldException("variable param can not be null for the provided searchBy parameter. Refer to method's Javadoc for more details.");
              }
-             body = "{\""+searchBy.name()+"\":\""+param+"\"}";
+             body = "{\""+searchBy.getKey()+"\":\""+param+"\"}";
              break;
      }
      final String endPoint = "/v1/invoices/search/";
diff --git a/src/main/java/com/trolley/trolley/InvoiceLine.java b/src/main/java/com/trolley/trolley/InvoiceLine.java
index 884ae9b..a5e58f0 100644
--- a/src/main/java/com/trolley/trolley/InvoiceLine.java
+++ b/src/main/java/com/trolley/trolley/InvoiceLine.java
@@ -1,6 +1,5 @@
 package com.trolley.trolley;
 
-import java.io.IOException;
 import java.util.List;
 import java.util.Locale;
 
diff --git a/src/main/java/com/trolley/trolley/Recipient.java b/src/main/java/com/trolley/trolley/Recipient.java
index bddce74..76952dd 100644
--- a/src/main/java/com/trolley/trolley/Recipient.java
+++ b/src/main/java/com/trolley/trolley/Recipient.java
@@ -6,8 +6,6 @@
 import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.annotation.JsonValue;
-import com.fasterxml.jackson.databind.ser.std.StdKeySerializers.Default;
-import com.trolley.trolley.Invoice.SearchBy;
 
 @JsonInclude(JsonInclude.Include.NON_NULL)
 public class Recipient
diff --git a/src/test/java/com/trolley/sdk/integration/InvoiceTests.java b/src/test/java/com/trolley/sdk/integration/InvoiceTests.java
index 2c18111..e9e0161 100644
--- a/src/test/java/com/trolley/sdk/integration/InvoiceTests.java
+++ b/src/test/java/com/trolley/sdk/integration/InvoiceTests.java
@@ -48,7 +48,7 @@ public void testInvoices() throws Exception {
             }
         };
 
-        // Create a new invoice - request body
+        // Create a new invoice - prepare request body
         Invoice invoice = new Invoice();
         invoice.setRecipientId(recipient.getId());
         invoice.setInvoiceNumber("invoice-123");
@@ -56,7 +56,7 @@ public void testInvoices() throws Exception {
         invoice.setExternalId("ext-id-"+System.currentTimeMillis());
         invoice.setLines(invoiceLines);
 
-        // Create a new invoice - receiving response
+        // Create a new invoice - send request and receive response
         invoice = client.invoice.create(invoice);
         assertEquals(invoice.getRecipientId(), recipient.getId());
 
@@ -84,7 +84,7 @@ public void testInvoices() throws Exception {
         Invoices invoices = client.invoice.search(Invoice.SearchBy.RECIPIENT_ID, recipientIds, null,1,2);
         List<Invoice> invoiceList = invoices.getInvoices();
         assertEquals(invoiceList.get(0).getRecipientId(),invoice.getRecipientId());
-        assertTrue(invoices.getMeta().getPages()>1);
+        assertTrue(invoices.getMeta().getPages() >= 1);
 
         //Cleanup - Delete Recipient
         boolean recDelResult = testHelper.deleteRecipient(recipient);