Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu cac » hieu luc, hieu va, hieu van
danh sai » dung sai, danh bat, danh dau
hieu cao » chieu cao, hieu ca, kieu cao
danh di » danh du, xanh di, danh dien
truc va » thuc va, thuc vat, trung va
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ty nang xa hoi. ((hieu cao) OR (hieu cac)) cau truc va ((danh sai) or (danh di)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty nang xa hoi. ((hieu cao) OR (hieu cac)) cau truc va ((danh sai) OR (danh di)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ty nang xa hoi. ((hieu cao) OR (hieu cac)) cau truc va ((danh sai) or (danh di)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ty nang xa hoi. ((hieu cao) OR (hieu cac)) cau truc va ((danh sai) or (danh di)) cua tre*.