Perhaps you should try some spelling variations:
"trinh van hau snippets" » "trinh han hau snippets", "trinh quan hau snippets", "trinh toan hau snippets", "trinh van ha snippets", "trinh van hai snippets", "trinh van dau snippets", "trinh van hau slippers"
"dung cua code snippets" » "dung luan code snippets", "dung cho code snippets", "dung cua cong snippets", "dung cua co snippets", "dung cfd code snippets", "dung cua 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: (((("trinh van hau snippets") or ("dung cua code snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("trinh van hau snippets") OR ("dung cua code snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( trinh van hau snippets ) or ( dung cua code snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("trinh van hau snippets") or ("dung cua code snippets"))) or ("locating bug code snippets"))*.