Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
nang cap » nang cao, nang cham, nang phap
hoi cua » hoi chuc
hai cua » thai cua, dai cua, lai cua
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
sach ky » sach y, sach ty, sach kem
hieu ve » hieu va, hieu van
cap hoi » cap phoi, cau hoi, cap voi
sac ky » cac ky, sai ky
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ky) OR (sac ky)) nang cap hoi. hieu ve cam thuc va hanh ((hai cua) or (hoi cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sac ky)) nang cap hoi. hieu ve cam thuc va hanh ((hai cua) OR (hoi cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) OR (sac ky)) nang cap hoi. hieu ve cam thuc va hanh ((hai cua) or (hoi cua)) tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) OR (sac ky)) nang cap hoi. hieu ve cam thuc va hanh ((hai cua) or (hoi cua)) tre*.