Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
van cham » van tham, va cham, van pham
van chat » cao chat
cau tren » cu tren, dau tren, ca tren
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
tuc va » thuc va, truc va, tuc xa
va cau » van cau, va cac, va dau
x hoi » xa hoi, o hoi, x ho

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 ky nang x hoi. hieu ((van cham) or (van chat)) tuc va hanh va cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ky nang x hoi. hieu ((van cham) OR (van chat)) tuc va hanh va cau tren.
• Adding a wildcard symbol may retrieve word variants: hoc sach ky nang x hoi. hieu ((van cham) or (van chat)) tuc va hanh va cau tren*.