diff --git a/object/search_default.go b/object/search_default.go
index a6b7283..399d0a2 100644
--- a/object/search_default.go
+++ b/object/search_default.go
@@ -33,8 +33,12 @@ func (p *DefaultSearchProvider) Search(qVector []float32) ([]Vector, error) {
 		vectorData = append(vectorData, candidate.Data)
 	}
 
+	similarities, err := getNearestVectors(qVector, vectorData, 5)
+	if err != nil {
+		return nil, err
+	}
+
 	res := []Vector{}
-	similarities := getNearestVectors(qVector, vectorData, 5)
 	for _, similarity := range similarities {
 		vector := vectors[similarity.Index]
 		vector.Score = similarity.Similarity
diff --git a/object/search_default_util.go b/object/search_default_util.go
index 59a61f2..107679a 100644
--- a/object/search_default_util.go
+++ b/object/search_default_util.go
@@ -15,6 +15,7 @@
 package object
 
 import (
+	"fmt"
 	"math"
 	"sort"
 )
@@ -53,11 +54,15 @@ type SimilarityIndex struct {
 	Index      int
 }
 
-func getNearestVectors(target []float32, vectors [][]float32, n int) []SimilarityIndex {
+func getNearestVectors(target []float32, vectors [][]float32, n int) ([]SimilarityIndex, error) {
 	targetNorm := norm(target)
 
 	similarities := []SimilarityIndex{}
 	for i, vector := range vectors {
+		if len(target) != len(vector) {
+			return nil, fmt.Errorf("The target vector's length: [%d] should equal to knowledge vector's length: [%d], target vector = %v, knowledge vector = %v", len(target), len(vector), target, vector)
+		}
+
 		similarity := cosineSimilarity(target, vector, targetNorm)
 		similarities = append(similarities, SimilarityIndex{similarity, i})
 	}
@@ -66,10 +71,9 @@ func getNearestVectors(target []float32, vectors [][]float32, n int) []Similarit
 		return similarities[i].Similarity > similarities[j].Similarity
 	})
 
-	if len(vectors) < n {
-		n = len(vectors)
+	if n > len(similarities) {
+		n = len(similarities)
 	}
-
 	res := similarities[:n]
-	return res
+	return res, nil
 }
diff --git a/object/vector_embedding.go b/object/vector_embedding.go
index 7e1f22b..f07db19 100644
--- a/object/vector_embedding.go
+++ b/object/vector_embedding.go
@@ -166,7 +166,7 @@ func GetNearestKnowledge(embeddingProvider *Provider, embeddingProviderObj embed
 	if err != nil {
 		return "", nil, err
 	}
-	if qVector == nil {
+	if qVector == nil || len(qVector) == 0 {
 		return "", nil, fmt.Errorf("no qVector found")
 	}