Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
nang cau » nang cao, hang cau, nang dau
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
thanh ve » hanh ve, thanh va, thanh vien
cau tren » cu tren, dau tren, ca tren
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
van cau » van dau, van hau, van chat
cau luc » cau truc, cau phuc
cuu tre » cua tre, cau treo
luc va » duc va, tuc va, loc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ty nang cau hoi. hieu van cau luc va thanh ve ((cuu tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ty nang cau hoi. hieu van cau luc va thanh ve ((cuu tre) OR (cau tren)).
• Adding a wildcard symbol may retrieve word variants: hoc sach ty nang cau hoi. hieu van cau luc va thanh ve ((cuu tre) or (cau tren))*.