Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
dau tren » dau tien, dat tren, dau tieng
cham tuc » nham thuc, tham thuc, cham soc
hieu va » lieu va, hieu qua
nang xa » lang xa, nang ma, mang xa
sac ky » cac ky, sai ky
va dan » ca dan, va dao, va dau
dan ve » ban ve, dan va, dan viet
ve dau » va dau, ve du, ke dau
tu sac » tu sach, tu cac, tu san

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 (nang x)) hoi. hieu va ((cham tuc) OR (pham thuc)) va dan ve dau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang xa) OR (nang x)) hoi. hieu va ((cham tuc) OR (pham thuc)) va dan ve dau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky ((nang xa) or (nang x)) hoi. hieu va ((cham tuc) OR (pham thuc)) va dan ve dau tren".
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang xa) or (nang x)) hoi. hieu va ((cham tuc) OR (pham thuc)) va dan ve dau tren*.