Perhaps you should try some spelling variations:
"trinh viet hoe snippets" » "ninh viet hoe snippets", "trinh vat hoe snippets", "trinh viet hien snippets", "trinh viet hoan snippets", "trinh viet khoa 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 java java snippets") or ("trinh viet hoe snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dung java java snippets") OR ("trinh viet hoe snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dung java java snippets ) or ( trinh viet hoe snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dung java java snippets") or ("trinh viet hoe snippets"))) or ("locating bug code snippets"))*.