Perhaps you should try some spelling variations:
"trinh vat con snippets" » "trinh van con snippets", "trinh luat con snippets", "sinh vat con snippets", "trinh va con snippets", "trinh vat co snippets", "trinh vit con 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 vat con 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 vat con snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( trinh vat con snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("trinh vat con snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.