Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
doc sach » hoc sach, toc sach, nuoc sach
hieu van » hieu va, thien van, lieu va
van tham » van thanh, van tuan, van chat
viet cua » viec cua, viet ca, biet cua
viet qua » vien quan, ket qua, viet ha
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
thuc va » thuc vat, thuc dan, thuc day
va danh » va dinh, va dan, va hanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach ky nang xa hoi. hieu van tham thuc va danh ((viet cua) OR (viet qua)) tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc sach ky nang xa hoi. hieu van tham thuc va danh ((viet cua) OR (viet qua)) tre".
• Adding a wildcard symbol may retrieve word variants: doc sach ky nang xa hoi. hieu van tham thuc va danh ((viet cua) OR (viet qua)) tre*.