Perhaps you should try some spelling variations:
"co trinh cad snippets" » "co trinh cau snippets", "co trinh cac snippets", "co trinh cam snippets", "co tranh cad snippets", "cong trinh cad snippets", "tao trinh cad 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: (((("co trinh cad snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("co trinh cad snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( co trinh cad snippets ) or ( dung java java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("co trinh cad snippets") or ("dung java java snippets"))) or ("locating bug code snippets"))*.