Perhaps you should try some spelling variations:
"dong dan canh snippets" » "dong dan code snippets", "dong danh canh snippets", "duong dan canh snippets", "dong san canh snippets", "dong van canh snippets", "dong dan cach snippets", "dong dan hanh 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 dan canh 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 dan canh snippets") OR ("dung java java snippets"))) OR ("locating bug core snippets")).
• Removing quotes may allow a broader search: (((( dong dan canh snippets ) or ( dung java java snippets ))) or ( locating bug core snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dong dan canh snippets") or ("dung java java snippets"))) or ("locating bug core snippets"))*.