Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
thanh lap » thanh san, phan lap, thanh hai
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van tham » van thanh, van tuan, van chat
va thanh » gia thanh, ban thanh, va tinh
sach ky » sac ky, sach y, sach ty
cao hoi » co hoi, cao hoc, tao hoi
thuc va » thuc vat, thuc dan, thuc day
lap cua » lai cua, tap cua, lam cua
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky nang ((cao hoi) or (cau hoi)). hieu van tham thuc va thanh lap cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang ((cao hoi) OR (cau hoi)). hieu van tham thuc va thanh lap cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang ((cao hoi) or (cau hoi)). hieu van tham thuc va thanh lap cua tre*.