diff --git a/dictsource/vi_rules b/dictsource/vi_rules
index b1633a19..b4279e91 100644
--- a/dictsource/vi_rules
+++ b/dictsource/vi_rules
@@ -94,7 +94,7 @@ ỵ	ỵ
 .group c
         c          k         //k
         c (C       _^_EN
-        c (_       k
+        c (_       c
      _) ch         tS       // try [tS;] [tS] [c] c     
 ?2   _) ch         c
 ?1   _) ch         c         
@@ -873,7 +873,7 @@ ỵ	ỵ
         ôi         oI
         ông        o#        // ông sound
 ?2      ôi         O-        //south dialect 
-        
+        ôc		   o#k
  
 
 .group ồ
@@ -891,7 +891,7 @@ ỵ	ỵ
         ối         oI3
         ống        o#3
 ?2      ối         O-3       
-        
+        ốc		   o#3k
  
         
  
@@ -921,7 +921,7 @@ ỵ	ỵ
         ội         oI6
    //     ộng        o#6
 ?2      ội         O-6       
-        
+        ộc         o#6k