Perhaps you should try some spelling variations:
tham thuc » nham thuc, tam thuc, thai thuc
pham thuc » phap thuc, pham chuc, nham thuc
toc sach » hoc sach, doc sach, thuoc sach
thi nang » thi cong, ki nang, thi hanh
van dinh » van minh, van dich, va dinh
dinh dau » dinh dat, dinh du, danh dau
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
dau cua » dai cua, day cua, cau 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 xa hoi. thi nang ((tham thuc) or (pham thuc)) van dinh dau cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang xa hoi. thi nang ((tham thuc) OR (pham thuc)) van dinh dau cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang xa hoi. thi nang ((tham thuc) or (pham thuc)) van dinh dau cua tre*.