Perhaps you should try some spelling variations:
"using cao cong snippets" » "using a cong snippets", "using two cong snippets", "using c cong snippets", "using cac cong snippets", "using cao dang snippets", "using cua cong snippets"
"hang java java snippets" » "hang va java snippets"
"locating bug code snippets" » "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("using cao cong snippets") or ("hang java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using cao cong snippets") OR ("hang java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using cao cong snippets ) or ( hang java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using cao cong snippets") or ("hang java java snippets"))) or ("locating bug code snippets"))*.