Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
via cua » gia cua, gian cua, giau cua
va hanh » va thanh, va danh, ban hanh
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
tu tong » tu tuong, tu trong, tu dong
tu tang » tuc tang, tu trang, tu lang
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 ((tu tang) OR (tu tong)) xa hoi. hieu ve cham soc ((van hanh) or (va hanh)) via cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((tu tang) OR (tu tong)) xa hoi. hieu ve cham soc ((van hanh) OR (va hanh)) via cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((tu tang) OR (tu tong)) xa hoi. hieu ve cham soc ((van hanh) or (va hanh)) via cua tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ((tu tang) OR (tu tong)) xa hoi. hieu ve cham soc ((van hanh) or (va hanh)) via cua tre*.