Perhaps you should try some spelling variations:
"thi tra trinh snippets" » "thi qua trinh snippets", "thi tran trinh snippets", "thi trac trinh snippets", "thi ra trinh snippets", "thi tra trinh slippers"
"dung java java snippets" » "dung va java snippets", "dung java java slippers"
"locating bug code snippets" » "locating bug code slippers", "locating bung code snippets", "locating bugs code snippets", "locating bug core snippets"

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"thi tra trinh snippets\") OR (\"dung java java snippets\"))) OR (\"locating bug code snippets\"))~".
• Removing quotes may allow a broader search: (((( thi tra trinh snippets ) OR ( dung java java snippets ))) OR ( locating bug code snippets ))~.
• Adding a wildcard symbol may retrieve word variants: (((("thi tra trinh snippets") OR ("dung java java snippets"))) OR ("locating bug code snippets"))*.