diff --git a/src/main/scala/de/upb/cs/swt/delphi/webapi/DelphiRoutes.scala b/src/main/scala/de/upb/cs/swt/delphi/webapi/DelphiRoutes.scala
index 683425a..83affe3 100644
--- a/src/main/scala/de/upb/cs/swt/delphi/webapi/DelphiRoutes.scala
+++ b/src/main/scala/de/upb/cs/swt/delphi/webapi/DelphiRoutes.scala
@@ -29,7 +29,7 @@ import de.upb.cs.swt.delphi.webapi.FeatureJson._
 import de.upb.cs.swt.delphi.webapi.IpLogActor._
 import de.upb.cs.swt.delphi.webapi.StatisticsJson._
 import de.upb.cs.swt.delphi.webapi.search.QueryRequestJson._
-import de.upb.cs.swt.delphi.webapi.search.{QueryRequest, SearchError, SearchQuery}
+import de.upb.cs.swt.delphi.webapi.search.{InvalidQueryError, QueryRequest, SearchError, SearchQuery}
 import spray.json._
 
 import scala.concurrent.duration._
@@ -113,6 +113,9 @@ class DelphiRoutes(requestLimiter: RequestLimitScheduler) extends JsonSupport wi
                 case se: SearchError => {
                   HttpResponse(StatusCodes.ServerError(StatusCodes.InternalServerError.intValue)(se.toJson.toString(), ""))
                 }
+                case iqe: InvalidQueryError => {
+                  HttpResponse(StatusCodes.ClientError(StatusCodes.BadRequest.intValue)(iqe.toJson.toString(), ""))
+                }
                 case _ => {
                   HttpResponse(StatusCodes.ServerError(StatusCodes.InternalServerError.intValue)("Search query failed", ""))
                 }
diff --git a/src/main/scala/de/upb/cs/swt/delphi/webapi/search/SearchQuery.scala b/src/main/scala/de/upb/cs/swt/delphi/webapi/search/SearchQuery.scala
index 64b56a8..bee7536 100644
--- a/src/main/scala/de/upb/cs/swt/delphi/webapi/search/SearchQuery.scala
+++ b/src/main/scala/de/upb/cs/swt/delphi/webapi/search/SearchQuery.scala
@@ -31,6 +31,7 @@ import scala.io.{Codec, Source}
 import scala.util.{Failure, Success, Try}
 import spray.json._
 import de.upb.cs.swt.delphi.webapi.FeatureJson._
+import org.parboiled2.{ParseError, Position}
 
 
 class SearchQuery(configuration: Configuration, featureExtractor: FeatureQuery) {
@@ -52,7 +53,7 @@ class SearchQuery(configuration: Configuration, featureExtractor: FeatureQuery)
     val publicFieldNames = internalFeatures.map(i => i.name)
     val invalidFields = fields.toSet.filter(f => !publicFieldNames.contains(f))
 
-    if (invalidFields.size > 0) return Failure(new IllegalArgumentException(s"Unknown field name(s) used. (${invalidFields.mkString(",")})"))
+    if (invalidFields.size > 0) return Failure(new InvalidQueryFieldsError(parsedQuery.toString, invalidFields))
 
     val translatedFields = fields.toSet.map(externalToInternalFeature(_))
     def getPrefix (in: String) : String = {
@@ -80,7 +81,7 @@ class SearchQuery(configuration: Configuration, featureExtractor: FeatureQuery)
 
     response match {
       case RequestSuccess(_, body, _, result) => Success(result.hits)
-      case r => Failure(new IllegalArgumentException(r.toString))
+      case r => Failure(new SearchError(f"Failed to query database: ${r.toString}"))
     }
   }
 
@@ -166,10 +167,17 @@ class SearchQuery(configuration: Configuration, featureExtractor: FeatureQuery)
     val validSize = size.exists(query.limit.getOrElse(defaultFetchSize) <= _)
     if (validSize) {
       val parserResult = new Syntax(query.query).QueryRule.run()
+
       parserResult match {
-        case Failure(e) => Failure(e)
+        case Failure(ParseError(Position(_, line, column), _, _)) =>
+          Failure(new InvalidQueryError(f"Syntax error in query (near line $line, column $column)", query.query))
+        case Failure(e) =>
+          Failure(e)
         case Success(parsedQuery) => {
           checkAndExecuteParsedQuery(parsedQuery, query.limit.getOrElse(defaultFetchSize)) match {
+            case Failure(e) if e.isInstanceOf[InvalidQueryFieldsError] =>
+              // Required to set a valid 'query' attribute to the error
+              Failure(new InvalidQueryFieldsError(query.query, e.asInstanceOf[InvalidQueryFieldsError].invalidFields))
             case Failure(e) => Failure(e)
             case Success(hits) => Success(ArtifactTransformer.transformResults(hits))
           }
@@ -177,7 +185,8 @@ class SearchQuery(configuration: Configuration, featureExtractor: FeatureQuery)
       }
     }
     else {
-      val errorMsg = new SearchError(s"Query limit exceeded default limit:  ${query.limit}>${size}")
+      val errorMsg = new InvalidQueryError(
+        s"Query limit exceeded default limit:  ${query.limit.getOrElse(defaultFetchSize)} > ${size.getOrElse("None")}", query.query)
       Failure(errorMsg)
     }
   }
diff --git a/src/main/scala/de/upb/cs/swt/delphi/webapi/search/package.scala b/src/main/scala/de/upb/cs/swt/delphi/webapi/search/package.scala
index e0b8189..42dc8cc 100644
--- a/src/main/scala/de/upb/cs/swt/delphi/webapi/search/package.scala
+++ b/src/main/scala/de/upb/cs/swt/delphi/webapi/search/package.scala
@@ -24,10 +24,29 @@ package object search {
 
   class SearchError(msg: String) extends RuntimeException(msg) with JsonSupport
 
+  class InvalidQueryError(val msg:String, val query: String) extends RuntimeException(msg) with JsonSupport
+
+  class InvalidQueryFieldsError(override val query: String, val invalidFields: Set[String])
+    extends InvalidQueryError("Query contained invalid query field names!", query)
+
   implicit val searchErrorWriter = new JsonWriter[SearchError] {
     override def write(obj: SearchError): JsValue = {
       JsObject("msg" -> JsString(obj.getMessage))
     }
   }
 
+  implicit val invalidQueryErrorWriter = new JsonWriter[InvalidQueryError] {
+    override def write(obj: InvalidQueryError): JsValue = {
+
+      obj match {
+        case error: InvalidQueryFieldsError =>
+          JsObject("msg" -> JsString(obj.getMessage), "query" -> JsString(obj.query),
+            "invalid_fields" -> JsArray(error.invalidFields.toVector.map(JsString(_))))
+        case _ =>
+          JsObject("msg" -> JsString(obj.getMessage), "query" -> JsString(obj.query))
+      }
+
+    }
+  }
+
 }