Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
vat hanh » vat thanh, van hanh, va hanh
cua viet » ca viet, cua vat, cua dieu
so sanh » do sanh
nang ma » tang ma, sang ma, nang cao
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sanh) or (cho sinh)) y nang ma hoi. hieu van cham thuc vat hanh vi ((cua viet) OR (hoa viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sanh) OR (cho sinh)) y nang ma hoi. hieu van cham thuc vat hanh vi ((cua viet) OR (hoa viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sanh) or (cho sinh)) y nang ma hoi. hieu van cham thuc vat hanh vi ((cua viet) OR (hoa viet))".
• Adding a wildcard symbol may retrieve word variants: ((so sanh) or (cho sinh)) y nang ma hoi. hieu van cham thuc vat hanh vi ((cua viet) OR (hoa viet))*.