Perhaps you should try some spelling variations:
"dung java java snippets" » "dung va java snippets"
"using ph cong snippets" » "using pre cong snippets", "using a cong snippets", "using _ cong snippets", "using phi cong snippets", "using pho cong snippets", "using phan cong 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 ph cong snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using ph cong snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using ph cong snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using ph cong snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.