Perhaps you should try some spelling variations:
tu sach » thu sach, te sach, tu cach
nang tu » nang du, nang luc
thu vat » thu va, thuat vat, thu nhat
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
su sach » so sach, vu sach
ma hoi » mai hoi, xa hoi, ma hoa
ve nam » he nam, va nam, le nam
tu cua » hu cua, vu cua
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: ((tu sach) or (su sach)) ky nang ma hoi. hieu ve nam ((thu vat) OR (thuc vat)) nang tu cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky nang ma hoi. hieu ve nam ((thu vat) OR (thuc vat)) nang tu cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ky nang ma hoi. hieu ve nam ((thu vat) OR (thuc vat)) nang tu cua te".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ky nang ma hoi. hieu ve nam ((thu vat) OR (thuc vat)) nang tu cua te*.