Perhaps you should try some spelling variations:
thanh son » thanh san, thanh cong, thanh toan
hieu cach » hieu cac, chieu sach, biet cach
phong lap » phong la, thong lap, phuong lan
phong lam » phuong lam, phong nam, thong lam
va trong » va truong, va thong, va tuong
cong van » cong vang, cong san, song van
hieu ca » hieu cac, hieu cua, hieu va
son va » song va, son la, lon va

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu cach) OR (hieu ca)) - thanh son va trong cong van ((phong lap) or (phong lam))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu cach) OR (hieu ca)) - thanh son va trong cong van ((phong lap) OR (phong lam)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu cach) OR (hieu ca)) - thanh son va trong cong van ((phong lap) or (phong lam))".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu cach) OR (hieu ca)) - thanh son va trong cong van ((phong lap) or (phong lam))*.