Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
dang cay » dang xay, dang ca, dang cac
cay phoi » cap phoi, tay hoi, cay cho
hang vi » hang va, hanh vi, hang di
va hang » van hang, va nang, va lang
ty dang » ty xang, ky dang, ty hang
luc va » duc va, tuc va, loc va
vi cua » vai cua, di cua
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: ((te sach) or (toc sach)) ty dang cay phoi. hieu ((van lam) or (van nam)) luc va hang vi cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ty dang cay phoi. hieu ((van lam) OR (van nam)) luc va hang vi cua tu.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ty dang cay phoi. hieu ((van lam) or (van nam)) luc va hang vi cua tu*.