Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
cham thuc » nham thuc, pham thuc, tham thuc
chat tre » chay tren, chat tai, cho tre
lam chat » luan chat, cao chat, ly chat
hanh lam » thanh lap, hanh kem, hanh va
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
su sach » so sach, vu sach

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) or (thuat sach)) ky ((nang x) or (nang ma)) hoi. hieu ve cham thuc va hanh lam chat tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (thuat sach)) ky ((nang x) OR (nang ma)) hoi. hieu ve cham thuc va hanh lam chat tre.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (thuat sach)) ky ((nang x) or (nang ma)) hoi. hieu ve cham thuc va hanh lam chat tre*.