Perhaps you should try some spelling variations:
chat truc » cau truc, chat xuc
hieu cao » chieu cao, hieu cac, hieu ca
sach ky » sach y, sach ty, sach kem
nang xa » nang x, lang xa, nang ma
va danh » va dan, va hanh, dia danh
va dinh » van dinh, va kinh, va tinh
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky

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) or (sac ky)) nang xa hoi. hieu cao chat truc ((va danh) OR (va dinh)) dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sac ky)) nang xa hoi. hieu cao chat truc ((va danh) OR (va dinh)) dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) or (sac ky)) nang xa hoi. hieu cao chat truc ((va danh) OR (va dinh)) dai cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) or (sac ky)) nang xa hoi. hieu cao chat truc ((va danh) OR (va dinh)) dai cua tre*.