Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
van hanh » van thanh, ban hanh, van anh
vai cuu » vai cua
va hanh » va thanh, va danh, ban hanh
hieu ve » hieu va, hieu van
sach ty » sach y, sach tu, xach tay
nang co » nang cao, nang doc, nang noi
cuu tre » cua tre, cau tren, cau treo
ve cam » ve cham, ve cac, va cam
co hoi » co hoc, co loi

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach ty) OR (sach thu)) nang co hoi. hieu ve cam xuc ((va hanh) or (van hanh)) vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach thu)) nang co hoi. hieu ve cam xuc ((va hanh) OR (van hanh)) vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) OR (sach thu)) nang co hoi. hieu ve cam xuc ((va hanh) or (van hanh)) vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) OR (sach thu)) nang co hoi. hieu ve cam xuc ((va hanh) or (van hanh)) vai cuu tre*.