Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
cac loc » cac lop, cac toc, cac hoc
dan van » dang van, doan van, dao van
loc va » hoc va, luc va
va dan » ca dan, va dao, va dau
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: ((tu sach) or (thuoc sach)) ky nang x ho. hieu va cac loc va dan van ((cua te) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuoc sach)) ky nang x ho. hieu va cac loc va dan van ((cua te) OR (cua tu)).
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuoc sach)) ky nang x ho. hieu va cac loc va dan van ((cua te) or (cua tu))*.