Perhaps you should try some spelling variations:
sach ky » sach y, sach ty, sach kem
hieu ve » hieu va, hieu van
kem cua » em cua, keo cua, diem cua
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
nang o » nang co, nang ho, nang ro
ve cam » ve cham, ve cac, va cam
xuc va » tuc va, luc va, xac va
o hoi » co hoi, o hoc, o hai

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 ky) or (sac ky)) nang o hoi. hieu ve cam ((xuc va) OR (duc va)) hanh kem cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang o hoi. hieu ve cam ((xuc va) OR (duc va)) hanh kem cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sac ky)) nang o hoi. hieu ve cam ((xuc va) OR (duc va)) hanh kem cua tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang o hoi. hieu ve cam ((xuc va) OR (duc va)) hanh kem cua tre*.