Perhaps you should try some spelling variations:
thuat thuc » thuat thuy, thuyet thuc, thuc thuc
chat thuc » nhan thuc, chat thai, chat huu
hieu van » hieu va, thien van, lieu va
hanh tai » thanh tai, hang tai, han tai
nang xa » nang x, lang xa, nang ma
sach ky » sach y, sach ty, sach kem
va hanh » van hanh, va thanh, va danh
tai cua » thai cua, tai cuc, tri cua
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: thu ((sach ky) or (sac ky)) nang xa hoi. hieu van ((chat thuc) OR (thuat thuc)) va hanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ky) OR (sac ky)) nang xa hoi. hieu van ((chat thuc) OR (thuat thuc)) va hanh tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ky) or (sac ky)) nang xa hoi. hieu van ((chat thuc) OR (thuat thuc)) va hanh tai cua tre".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ky) or (sac ky)) nang xa hoi. hieu van ((chat thuc) OR (thuat thuc)) va hanh tai cua tre*.