Perhaps you should try some spelling variations:
sach van » sach han, bach van, cach van
van hanh » van thanh, ban hanh, van anh
truc van » truc va, thuc van, truc ban
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
sach va » sach xa, sach ha, sach dao
ve cam » ve cham, ve cac, ve cai
va cam » va cham, va cac, va cao
di cua » dai cua, doi cua, de cua

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 van) OR (sach va)) nang x ho. hieu ((ve cam) or (va cam)) truc van hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach van) OR (sach va)) nang x ho. hieu ((ve cam) OR (va cam)) truc van hanh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach van) OR (sach va)) nang x ho. hieu ((ve cam) or (va cam)) truc van hanh di cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach van) OR (sach va)) nang x ho. hieu ((ve cam) or (va cam)) truc van hanh di cua tre*.