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