Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hoc truc » hoc thuc, hoc trung, hoc thuoc
so sach » so sanh, bo sach, co sach
nang ma » tang ma, sang ma, nang cao
van hoc » van hoa
truc xa » tuc xa, truc va, truoc xay
xa dinh » xac dinh, va dinh, ba dinh
dinh vi » dinh ve, dinh viet, dinh tri
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: so sach y ((nang x) or (nang ma)) hoi. hieu van hoc truc xa dinh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y ((nang x) OR (nang ma)) hoi. hieu van hoc truc xa dinh vi cua tre*.