Perhaps you should try some spelling variations:
"manh chung do snippets" » "manh hung do snippets", "lanh chung do snippets", "doanh chung do snippets", "manh chung co snippets", "manh chung o snippets", "manh nhung don 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: (((("manh chung do snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("manh chung do snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( manh chung do snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("manh chung do snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.