Perhaps you should try some spelling variations:
"trinh dan da snippets" » "trinh han da snippets", "trinh van da snippets", "trinh san da snippets", "trinh dan dat snippets", "trinh dan ca snippets", "trinh dan va 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: (((("trinh dan da snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("trinh dan da snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( trinh dan da snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("trinh dan da snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.