Perhaps you should try some spelling variations:
"doi thieu cac snippets" » "doi chieu cac snippets", "gioi thieu cac snippets", "toc thieu cac snippets", "doi hieu cac snippets", "doi thien cac snippets", "doi hieu ca 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: (((("doi thieu cac snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("doi thieu cac snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( doi thieu cac snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("doi thieu cac snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.