Perhaps you should try some spelling variations:
"trong tin co snippets" » "thong tin co snippets", "trong tan co snippets", "trong tieng co snippets", "trong tinh co snippets", "trong tin so snippets", "trong tinh cao 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: (((("trong tin co snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("trong tin co snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( trong tin co snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("trong tin co snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.