Perhaps you should try some spelling variations:
"duong xuan can snippets" » "dong xuan can snippets", "luong xuan can snippets", "duong quan can snippets", "duong xuan cang snippets", "duong xuan tan snippets", "duong xuan chanh 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: (((("duong xuan can snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("duong xuan can snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( duong xuan can snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("duong xuan can snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.