Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
tham duc » pham duc, tham du, than duc
ban hanh » ban hang
sach ky » sac ky, sach y, sach ty
va tham » van tham, va cham, va thanh
duc ban » duc tan, duc van, dua ban
doi cua » dai cua, hoi cua
di cua » dai cua, de cua, do cua
o hoc » co hoc, mo hoc, so hoc

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 ((o hoc) or (xa hoi)). lieu va tham duc ban hanh ((di cua) OR (doi cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ky nang ((o hoc) OR (xa hoi)). lieu va tham duc ban hanh ((di cua) OR (doi cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ky nang ((o hoc) or (xa hoi)). lieu va tham duc ban hanh ((di cua) OR (doi cua)) triet".
• Adding a wildcard symbol may retrieve word variants: hoc sach ky nang ((o hoc) or (xa hoi)). lieu va tham duc ban hanh ((di cua) OR (doi cua)) triet*.