diff --git a/src/util.jl b/src/util.jl
index 624f873..ab4b4b7 100644
--- a/src/util.jl
+++ b/src/util.jl
@@ -284,7 +284,10 @@ function textToDict(text::String, keywords::Vector{String};
   kw = []
   # use for loop and detect_keyword function to get the exact variation of each keyword in the text then push to kw list
   for keyword in keywords
-    push!(kw, detect_keyword(keyword, text))
+    detected = detect_keyword(keyword, text)
+    if detected !== nothing
+      push!(kw, detected)
+    end
   end
 
   od1, od2 =