Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh tai » thanh tai, hang tai, han tai
truc van » truc va, thuc van, truc ban
hieu van » hieu va, thien van, lieu va
tai cua » thai cua, tai cuc, tri cua
tuc van » thuc van, tuc va, duc van
van cam » van nam, van lam, van cau
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky ((nang xa) or (nang ma)) hoi. hieu van cam ((tuc van) OR (truc van)) hanh tai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky ((nang xa) OR (nang ma)) hoi. hieu van cam ((tuc van) OR (truc van)) hanh tai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky ((nang xa) or (nang ma)) hoi. hieu van cam ((tuc van) OR (truc van)) hanh tai cua te".
• Adding a wildcard symbol may retrieve word variants: toc sach ky ((nang xa) or (nang ma)) hoi. hieu van cam ((tuc van) OR (truc van)) hanh tai cua te*.