Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
trinh dai » trinh di, trinh da, trinh dan
trinh tai » trinh toan, trinh tu, trinh han
hieu van » hieu va, thien van, lieu va
van chao » van chat, van hao, van cho
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet
xu va » xu van, tu va, su va

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 ky nang xa hoi. hieu van chao xu va ((trinh dai) OR (trinh tai)) cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ky nang xa hoi. hieu van chao xu va ((trinh dai) OR (trinh tai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thuat sach ky nang xa hoi. hieu van chao xu va ((trinh dai) OR (trinh tai)) cua tre*.