Perhaps you should try some spelling variations:
"dong cao cach snippets" » "dong cao code snippets", "duong cao cach snippets", "dong co cach snippets", "dong cho cach snippets", "dong cai cach snippets", "dong cac cach snippets", "dong ca cach 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 cao 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 cao cach snippets") OR ("dung java java snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( dong cao cach snippets ) or ( dung java java snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dong cao cach snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))*.