Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
cua tre » cua te, cuu tre, cua triet
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
va tham » van tham, va cham, va thanh
hieu va » lieu va, hieu qua
vi cua » vai cua, di cua
tu sac » tu sach, tu cac, tu bac
nang o » nang co, nang ho, nang ro
tu ban » thu ban, te ban
tu san » thu san, tu can, vu san
o hoi » co hoi, o hoc, o hai

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

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