Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
chat duc » chat xuc, chat doc, chet duoc
hang di » hang doi, hang vi, hang dien
va hang » van hang, va nang, va lang
va chat » van chat, va phat, cao chat
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
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 nang xa hoi. hieu va chat duc va hang di ((cua te) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ty nang xa hoi. hieu va chat duc va hang di ((cua te) OR (cua tu)).
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ty nang xa hoi. hieu va chat duc va hang di ((cua te) or (cua tu))*.