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