Perhaps you should try some spelling variations:
"thanh tung code snippets" » "thanh cong code snippets", "thanh tung code slippers"
"using cfd code snippets" » "using 3d code snippets", "using c code snippets", "using cfd 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: (((("using cfd code snippets") or ("thanh tung code snippets"))) or ("locating bug code snippets"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("using cfd code snippets") OR ("thanh tung code snippets"))) OR ("locating bug code snippets")).
• Removing quotes may allow a broader search: (((( using cfd code snippets ) or ( thanh tung code snippets ))) or ( locating bug code snippets )).
• Adding a wildcard symbol may retrieve word variants: (((("using cfd code snippets") or ("thanh tung code snippets"))) or ("locating bug code snippets"))*.