Perhaps you should try some spelling variations:
"can trinh tu snippets" » "can tranh tu snippets", "dan trinh tu snippets", "van trinh tu snippets", "can trinh ky snippets", "can trinh do snippets", "can trinh tu slippers"
"dung nhan code snippets" » "dung luan code snippets", "dung nhan co snippets", "dung nhan con snippets", "dung nhan code slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code 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: (((("can trinh tu snippets") or ("dung nhan code snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("can trinh tu snippets") OR ("dung nhan code snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( can trinh tu snippets ) or ( dung nhan code snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("can trinh tu snippets") or ("dung nhan code snippets"))) or ("locating bug code snippets"))*.