Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
so sach » so sanh, bo sach, co sach
hang vi » hang va, hanh vi, khang voi
hang di » hang doi, hang dien, hang dich
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
va cam » va cham, va cac, va cao
y lang » _ lang, tay lang, yen lang
ha hoi » hoa hoi, ha noi, xa hoi
o lang » hoa lang, hoi lang
thiet* » thieu*

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ((y lang) or (o lang)) ha hoi. hieu va cam thuc va ((hang di) OR (hang vi)) va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((y lang) OR (o lang)) ha hoi. hieu va cam thuc va ((hang di) OR (hang vi)) va thiet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((y lang) or (o lang)) ha hoi. hieu va cam thuc va ((hang di) OR (hang vi)) va thiet*".