Perhaps you should try some spelling variations:
thien van » thi van
cac tinh » dac tinh, cuu tinh, ha tinh
la trong » lam trong, lap trong, le trong
su sach » so sach, vu sach
tinh va » tich va, trinh van, trinh vat
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
va cua » va chua, via cua, ca 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 ky ((nang ma) or (sang ma)) hoi. ((lieu va) or (thien van)) la trong cac tinh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang ma) OR (sang ma)) hoi. ((lieu va) OR (thien van)) la trong cac tinh va cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky ((nang ma) or (sang ma)) hoi. ((lieu va) or (thien van)) la trong cac tinh va cua tre*.