Perhaps you should try some spelling variations:
"phap dinh may tinh f.c." » "phan dinh may tinh f.c.", "pham dinh may tinh f.c.", "phap sinh may tinh f.c.", "phap dinh may tinh hoc.", "phap dinh may tinh bac.", "phap dinh may tinh duc.", "phap trinh may tinh f.c.", "phap dinh moi tinh f.c.", "phap dinh lam tinh f.c."
"tham dinh van tinh f.c." » "thai binh van tinh f.c.", "than kinh van tinh f.c.", "pham minh van tinh f.c.", "tham dinh van thinh f.c.", "tham dinh van minh f.c.", "tham dinh ban tinh f.c.", "tham dinh van tinh hoc.", "tham dinh van tinh bac.", "tham dinh van tinh duc."
"nam dinh ban hanh f.c." » "nam dinh bang hanh f.c.", "nam dinh ba hanh f.c.", "nam sinh ban hanh f.c.", "nam dinh ban hang f.c.", "nam dinh ban hanh cac."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("tham dinh van tinh f.c.") or ("nam dinh ban hanh f.c."))) or ("phap dinh may tinh f.c."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("tham dinh van tinh f.c.") OR ("nam dinh ban hanh f.c."))) OR ("phap dinh may tinh f.c."))*.
• Removing quotes may allow a broader search: (((( tham dinh van tinh f.c. ) or ( nam dinh ban hanh f.c. ))) or ( phap dinh may tinh f.c. ))*.