Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
ve ban » te ban, va ban, ve bao
bao va » bao ve, tao va, ban va
vi cau » va cau, ve cau, di cau
x hoi » xa hoi, o hoi, x ho
bo va » do va, so va, co va

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 ky nang x hoi. hieu ve ban ((bo va) OR (bao va)) hanh vi cau tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang x hoi. hieu ve ban ((bo va) OR (bao va)) hanh vi cau tren".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang x hoi. hieu ve ban ((bo va) OR (bao va)) hanh vi cau tren*.