Perhaps you should try some spelling variations:
van tham » van thanh, van tuan, van chat
hieu van » hieu va, thien van, lieu va
van hoan » van hoang, van hoa, van toan
van doan » van doanh, van toan, van dan
tham so » ham so, tham do, than so
sach ty » sach y, sach tu, sach thu
tu sach » thu sach, su sach, te sach
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
cua tre » cua te, cuu tre, cua triet
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: tu sach ty ((nang xa) or (lang xa)) hoi. hieu van tham so ((van doan) or (van hoan)) va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty ((nang xa) OR (lang xa)) hoi. hieu van tham so ((van doan) OR (van hoan)) va cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach ty ((nang xa) or (lang xa)) hoi. hieu van tham so ((van doan) or (van hoan)) va cua tre*.