Perhaps you should try some spelling variations:
"dung dang toan snippets" » "dung dan toan snippets", "dung dong toan snippets", "dung danh toan snippets", "dung dang tran snippets", "dung dung toan snippets"
"dung java java snippets" » "dung 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: (((("dung dang toan snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung dang toan snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung dang toan snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung dang toan snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.