Perhaps you should try some spelling variations:
"dong tranh doc snippets" » "dong thanh doc snippets", "dong trinh doc snippets", "trong tranh doc snippets", "dong tranh duoc snippets", "dong tranh cuoc snippets"
"data using java snippets" » "data using data 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: (((("dong tranh doc snippets") or ("data using java snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("dong tranh doc snippets") OR ("data using java snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( dong tranh doc snippets ) or ( data using java snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("dong tranh doc snippets") or ("data using java snippets"))) or ("locating bug code snippets"))*.