Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
cac duc » cac du, cao duc, cac dac
sach ty » sach y, sach tu, xach tay
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
ve cac » va cac, vien cac
va anh » van anh, va danh, va hanh
va cua » va chua, via cua, ma cua
ca cua » co cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ty) OR (sach thu)) nang xa hoi. hieu ve cac duc va anh ((va cua) or (ca cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach thu)) nang xa hoi. hieu ve cac duc va anh ((va cua) OR (ca cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) OR (sach thu)) nang xa hoi. hieu ve cac duc va anh ((va cua) or (ca cua)) te".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) OR (sach thu)) nang xa hoi. hieu ve cac duc va anh ((va cua) or (ca cua)) te*.