Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
manh vai » manh hai, manh va, manh khai
dan manh » dang manh, doan manh, van manh
thuc dan » thuc hanh, hoc dan, thuc vat
nang xa » nang x, nang ma, mang xa
vai cua » dai cua, hai cua, lai cua
lang xa » lang ha, dang xay, lang van
tu sac » tu sach, tu cac, tu san
va nay » va ngay, va cay
sac ky » cac ky, sai ky
ve nam » he nam, va nam, le nam

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky ((nang xa) OR (lang xa)) hoi. hieu ((ve nam) or (va nay)) thuc dan manh vai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang xa) OR (lang xa)) hoi. hieu ((ve nam) OR (va nay)) thuc dan manh vai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky ((nang xa) OR (lang xa)) hoi. hieu ((ve nam) or (va nay)) thuc dan manh vai cua viet".
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang xa) OR (lang xa)) hoi. hieu ((ve nam) or (va nay)) thuc dan manh vai cua viet*.