Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
va thanh » gia thanh, ban thanh, va tinh
thuc va » thuc vat, thuc dan, thuc day
tu sach » thu sach, su sach, te sach
hieu he » hieu ve, hiem he, hieu le
he nam » ha nam, nghe nam
ve luu » ke luu
vi luu » vi lua
x hoi » xa hoi, o hoi, x ho

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 (thu hoach)) ky nang x hoi. hieu he nam thuc va thanh ((ve luu) OR (vi luu)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu hoach)) ky nang x hoi. hieu he nam thuc va thanh ((ve luu) OR (vi luu)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu hoach)) ky nang x hoi. hieu he nam thuc va thanh ((ve luu) OR (vi luu)) tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu hoach)) ky nang x hoi. hieu he nam thuc va thanh ((ve luu) OR (vi luu)) tre*.