Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
sach ty » sach y, sach tu, sach thu
hanh va » hang va, hanh vi
su sach » so sach, vu sach
ty hang » ly hang, ty xang, thi hang
ve cao » va cao, ve bao, ve co
ve cac » va cac, vien cac
hang x » nang x, hoang xa, chang xu
x hoi » xa hoi, o hoi, x ho

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 hang x hoi. hieu ((ve cao) OR (ve cac)) duc va ((hanh kem) or (hanh va)) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty hang x hoi. hieu ((ve cao) OR (ve cac)) duc va ((hanh kem) OR (hanh va)) cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty hang x hoi. hieu ((ve cao) OR (ve cac)) duc va ((hanh kem) or (hanh va)) cau tren".
• Adding a wildcard symbol may retrieve word variants: su sach ty hang x hoi. hieu ((ve cao) OR (ve cac)) duc va ((hanh kem) or (hanh va)) cau tren*.