Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
tinh tai » trinh tai, tinh thai, tinh hai
tai cua » thai cua, tai cuc, tri cua
va tinh » may tinh
hieu ha » hieu hoa, hieu va, hieu ca
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
cua tre » cua te, cuu tre, cua triet
nam tu » nam thuc

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach y ((nang xa) OR (nang ma)) hoi. hieu ha ((nam tu) or (nam thu)) va tinh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach y ((nang xa) OR (nang ma)) hoi. hieu ha ((nam tu) OR (nam thu)) va tinh tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach y ((nang xa) OR (nang ma)) hoi. hieu ha ((nam tu) or (nam thu)) va tinh tai cua tre".
• Adding a wildcard symbol may retrieve word variants: thuat sach y ((nang xa) OR (nang ma)) hoi. hieu ha ((nam tu) or (nam thu)) va tinh tai cua tre*.