diff --git a/View/mainwindow.py b/View/mainwindow.py
index da13162..74d3332 100644
--- a/View/mainwindow.py
+++ b/View/mainwindow.py
@@ -280,7 +280,7 @@ class Ui_MainWindow(object):
         proc.waitForFinished()
 
         if proc.exitCode() != 0:
-            print(f"'sqlitebrowser' return with error code : {proc.exitCode()}")
+            print(f"'sqlitebrowser' return with error code: {proc.exitCode()}")
             print("-error------")
             print(f"{proc.readAllStandardError()}")
             print("------------")
@@ -290,17 +290,29 @@ class Ui_MainWindow(object):
         aw = AboutWindow()
         aw.exec()
 
+    def current_file_path(self, filename):
+        return os.path.abspath(
+            os.path.join(
+                os.path.dirname(__file__),
+                "..", filename
+            )
+        )
+
+    def open_doc_file(self, filename):
+        QtGui.QDesktopServices.openUrl(
+            QtCore.QUrl(
+                f"file://{self.current_file_path(filename)}"
+            )
+        )
+
     def user_manual(self):
-        open('AcouSed_UserManual.pdf')
-        run(["open", 'AcouSed_UserManual.pdf'])
+        self.open_doc_file('AcouSed_UserManual.pdf')
 
     def inversion_acoustic_theory(self):
-        open('Acoustic_Inversion_theory.pdf')
-        run(["open", 'Acoustic_Inversion_theory.pdf'])
+        self.open_doc_file('Acoustic_Inversion_theory.pdf')
 
     def tutorial_AQUAscat_software(self):
-        open('Tutorial_AQUAscat_software.pdf')
-        run(["open", 'Tutorial_AQUAscat_software.pdf'])
+        self.open_doc_file('Tutorial_AQUAscat_software.pdf')
 
     def export_table_of_acoustic_BS_values_to_excel_or_libreOfficeCalc_file(self):