diff --git a/include/library.h b/include/library.h
index 0d5d19f0f..ef43f2a7e 100644
--- a/include/library.h
+++ b/include/library.h
@@ -141,6 +141,22 @@ private: // functions
     bool accept(const Book& book) const;
 };
 
+
+class ZimSearcher : public zim::Searcher
+{
+  public:
+    explicit ZimSearcher(zim::Searcher&& searcher)
+      : zim::Searcher(searcher)
+    {}
+
+    std::unique_lock<std::mutex> getLock() {
+      return std::unique_lock<std::mutex>(m_mutex);
+    }
+    virtual ~ZimSearcher() = default;
+  private:
+    std::mutex m_mutex;
+};
+
 /**
  * A Library store several books.
  */
@@ -209,10 +225,10 @@ class Library
 
   DEPRECATED std::shared_ptr<Reader> getReaderById(const std::string& id);
   std::shared_ptr<zim::Archive> getArchiveById(const std::string& id);
-  std::shared_ptr<zim::Searcher> getSearcherById(const std::string& id) {
+  std::shared_ptr<ZimSearcher> getSearcherById(const std::string& id) {
     return getSearcherByIds(BookIdSet{id});
   }
-  std::shared_ptr<zim::Searcher> getSearcherByIds(const BookIdSet& ids);
+  std::shared_ptr<ZimSearcher> getSearcherByIds(const BookIdSet& ids);
 
   /**
    * Remove a book from the library.
diff --git a/src/library.cpp b/src/library.cpp
index d4b933c4d..ad97a0c38 100644
--- a/src/library.cpp
+++ b/src/library.cpp
@@ -93,7 +93,7 @@ struct Library::Impl
   std::map<std::string, Entry> m_books;
   using ArchiveCache = ConcurrentCache<std::string, std::shared_ptr<zim::Archive>>;
   std::unique_ptr<ArchiveCache> mp_archiveCache;
-  using SearcherCache = MultiKeyCache<std::string, std::shared_ptr<zim::Searcher>>;
+  using SearcherCache = MultiKeyCache<std::string, std::shared_ptr<ZimSearcher>>;
   std::unique_ptr<SearcherCache> mp_searcherCache;
   std::vector<kiwix::Bookmark> m_bookmarks;
   Xapian::WritableDatabase m_bookDB;
@@ -304,7 +304,7 @@ std::shared_ptr<zim::Archive> Library::getArchiveById(const std::string& id)
   }
 }
 
-std::shared_ptr<zim::Searcher> Library::getSearcherByIds(const BookIdSet& ids)
+std::shared_ptr<ZimSearcher> Library::getSearcherByIds(const BookIdSet& ids)
 {
   assert(!ids.empty());
   try {
@@ -318,7 +318,7 @@ std::shared_ptr<zim::Searcher> Library::getSearcherByIds(const BookIdSet& ids)
         }
         archives.push_back(*archive);
       }
-      return std::make_shared<zim::Searcher>(archives);
+      return std::make_shared<ZimSearcher>(zim::Searcher(archives));
     });
   } catch (std::invalid_argument&) {
     return nullptr;
diff --git a/src/server/internalServer.cpp b/src/server/internalServer.cpp
index c4f6fd7cb..0a61f0ee4 100644
--- a/src/server/internalServer.cpp
+++ b/src/server/internalServer.cpp
@@ -704,11 +704,13 @@ std::unique_ptr<Response> InternalServer::handle_search(const RequestContext& re
 
     /* Make the search */
     // Try to get a search from the searchInfo, else build it
+    auto searcher = mp_library->getSearcherByIds(bookIds);
+    auto lock(searcher->getLock());
+
     std::shared_ptr<zim::Search> search;
     try {
       search = searchCache.getOrPut(searchInfo,
         [=](){
-          auto searcher = mp_library->getSearcherByIds(bookIds);
           return make_shared<zim::Search>(searcher->search(searchInfo.getZimQuery(m_verbose.load())));
         }
       );