Perhaps you should try some spelling variations:
sach nham » sach nha, sach tham, sach han
thanh va » thanh van, hanh va, thanh ha
thanh vi » hanh vi, thanh ve, nhanh vi
su sach » so sach, vu sach
duc gia » quoc gia
cam duc » cam xuc, cao duc, pham duc
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
sang ma » tang ma, nang ma, sang tao
ve cam » ve cham, ve cac, va cam

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 nham ((sang ma) or (nang cao)) hoi. hieu ve cam duc gia ((thanh vi) OR (thanh va)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach nham ((sang ma) OR (nang cao)) hoi. hieu ve cam duc gia ((thanh vi) OR (thanh va)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach nham ((sang ma) or (nang cao)) hoi. hieu ve cam duc gia ((thanh vi) OR (thanh va)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach nham ((sang ma) or (nang cao)) hoi. hieu ve cam duc gia ((thanh vi) OR (thanh va)) cua tre*.