Perhaps you should try some spelling variations:
"dang vat code snippets" » "dang van code snippets", "dong vat code snippets", "dang nhat code snippets", "dang rate code snippets", "dang vat co snippets", "dang vat de snippets", "dang vat code slippers"
"dung hoc code snippets" » "dong hoc code snippets", "dung thuoc code snippets", "trung hoc code snippets", "dung hoc co snippets", "dung hoc cong snippets", "dung hoc de snippets", "dung hoc code slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code 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: (((("dang vat code snippets") or ("dung hoc code snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dang vat code snippets") OR ("dung hoc code snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dang vat code snippets ) or ( dung hoc code snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dang vat code snippets") or ("dung hoc code snippets"))) or ("locating bug code snippets"))*.