Perhaps you should try some spelling variations:
"dung quang can snippets" » "dang quang can snippets", "luong quang can snippets", "dung luan can snippets", "dung quang chan snippets", "dung quang cao snippets", "dung quang ban snippets"
"hanh java java snippets" » "hanh 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: (((("hanh java java snippets") or ("dung quang can snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("hanh java java snippets") OR ("dung quang can snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( hanh java java snippets ) or ( dung quang can snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("hanh java java snippets") or ("dung quang can snippets"))) or ("locating bug code snippets"))*.