Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh tai » thanh tai, hang tai, han tai
nang xa » lang xa, nang ma, mang xa
sach ky » sac ky, sach ty, sach kem
van cam » van nam, van lam, van cau
cam tuc » cam xuc, cam tu, nam thuc
va hanh » van hanh, va thanh, va danh
tai cua » thai cua, tai cuc, tri cua
tuc va » thuc va, truc va, tuc xa
cua tu » cua tuc, cua su, cua cu

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) OR (sach y)) ((nang xa) or (nang x)) hoi. hieu van cam tuc va hanh tai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((sach ky) OR (sach y)) ((nang xa) OR (nang x)) hoi. hieu van cam tuc va hanh tai cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((sach ky) OR (sach y)) ((nang xa) or (nang x)) hoi. hieu van cam tuc va hanh tai cua tu".
• Adding a wildcard symbol may retrieve word variants: doc ((sach ky) OR (sach y)) ((nang xa) or (nang x)) hoi. hieu van cam tuc va hanh tai cua tu*.